Secrets of the Dead (2000–…): Season 17, Episode 2 - Hannibal in the Alps - full transcript
Explorers, archaeologists and scientists combine technology and ancient texts to prove that Hannibal's army crossed the Alps to launch an attack on Rome.
♪♪
-218 B.C. -- a young general
leads a vast army across Europe
in a surprise attack
on the Roman Republic.
In his path lies an almost
impossible challenge --
the foreboding Alps.
-When they arrived
at the mountains
and they began to climb,
the full enormity
of the task ahead
sunk into the soldiers.
The ancient writers talk about
the way that the soldiers
considered these mountains
to be almost supernatural.
♪♪
-It is only their belief
in their daring commander
that keeps them going.
That man is the legend
of Carthage -- Hannibal Barca.
And that winter, he embarked
on one of the most audacious
military feats in history --
the crossing
of the French Alps into Italy
with a force of almost
40,000 soldiers,
9,000 cavalry,
and, perhaps most famous of all,
37 elephants.
-I just find it
so improbable
elephants passing through here.
-But no one has ever found
a single piece
of physical evidence
marking Hannibal's exact route.
Now, an international team
of scientists and historians
are determined to uncover where
Hannibal made his epic march.
-It was an absolute
revelation for us.
-I felt elated.
I'd never seen
anything like that.
I mean, this isn't what happens.
-And they will recreate
the journey...
-Stop there.
It's really icy.
I don't think we can go there.
We have to find another way.
-...to discover how
Hannibal conquered
the fearsome mountains.
"Hannibal in the Alps."
♪♪
[ Wind blowing ]
-The Alps.
80,000 square miles
of desolate,
hostile mountain terrain.
And not a trace
of the extraordinary events
that took place here
over 2,000 years ago.
Hannibal's exact route has
remained an enduring mystery.
♪♪
As the turn of the first
millennium approached,
the two superpowers
of Carthage in North Africa
and the Roman Republic
were preparing for war.
Fearing a Roman invasion
of Carthage,
Hannibal drew up plans
for a daring surprise attack.
Instead of launching
an invasion by sea,
he would lead an army
across the French Alps,
sweep through Italy,
and take on the might of Rome.
Historian Eve MacDonald
has spent her career
following the trail of Hannibal,
fascinated by the man himself.
-Getting inside the minds of
people who lived 2,000 years ago
is so difficult.
Even in Roman times,
just after the events,
there was controversy
over which pass
Hannibal took over the Alps.
-What is known about his path
comes from ancient writers
who recorded the events
two millennia ago.
-Polybius is our best source
by a long way.
Polybius wrote about 60 years
after Hannibal crossed the Alps.
Now, he had access
to eyewitnesses
who were with Hannibal.
And that is why he's probably
our most valuable source.
-In his account of Hannibal's
crossing of the Alps,
Polybius mentions numerous
geographical features
encountered along the route.
-The sight of Italy
clearly spread out below.
The fresh fall
of this year's snow.
A landslide made worse
by a second
and more recent landslip.
-We can use these texts
almost as guides
to go into the mountains
and try and piece together
an accurate account
of the route which he took.
-Eve is joining
geologist Bill Mahaney
to find where Hannibal actually
went across the mountains.
-I'm a mountaineer.
In the old days,
I went climbing.
Later days, I did geology.
That's what I do.
-Bill is convinced
the mountains
must hold the key.
His team is searching
for microscopic clues
buried beneath the surface...
-It's a good one.
-Got 50 centimeters of different
environmental change.
Fantastic.
-Bill does not believe
an enormous army
could have moved
through the mountains
without leaving
something behind,
and he is determined to find it.
For him, discovering the truth
about Hannibal's
mountain crossing
is a lifelong obsession.
-He was a mountain man.
He tackled a mountain
experience that
absolutely floors me.
I've been in the mountains
with 100, 150 people.
It's pandemonium.
People fall in crevasses,
people get lost off snowmobiles,
people get killed.
It's crazy.
And he took 30,000 men,
37 elephants,
and God knows how many horses
across one of the imposing
mountains in the world.
You have to admit
this man was --
he knew what he was doing,
and he was a man of some genius
to be able to pull it off.
♪♪
-Hannibal came from a family
of generals and statesmen
and he was raised to see Rome
as a mortal enemy.
Historian Nejib Ben Lazreg
is from Tunisia,
the same area as Carthage,
where Hannibal's legacy
is still very much alive.
-Hannibal was brought up
in a family of
military figures
like his father Hamilcar Barca,
who defeated the Romans
in big battles in Sicily,
and the mercenaries in Africa
when they rebelled
against Carthage.
-Inheriting his father's
strategic brilliance,
Hannibal gave Carthage
its most glorious hour.
-He was a very skilled man.
And he had the ability to spot
the good place where he could
trap the enemy.
I consider that he is the
greatest figure in our history.
[ Wind howling ]
-No one knows
Hannibal's exact path,
but based on Polybius
and other ancient guides,
four main routes across
the Alps are possible --
two northern routes over
the Col du Mont Cenis
or the Col de Clapier --
one running through the center
and over
the Col de Montgenèvre
and a southern route--
the highest and most dangerous
of all --
over the Col de la Traversette.
And Bill believes
it's this southern pass
Hannibal used to march his army
into enemy territory.
It's a route so treacherous
that most historians
have dismissed it as impossible.
But Bill wants to prove
the historians wrong.
-I mean, if that is
the Hannibal layer,
that's perfect.
-Polybius tells us that Hannibal
rested his army for a few days
at key points along the route.
The team hopes the troops
stayed long enough
to have left their mark
on the land.
-They established a resting camp
for two days
that gave the soldiers
a breathing space
in which to recover.
-Bill believes
this open area below the pass
could be
one of those resting places.
-Just imagine the troops
moving down through here
would have basically covered
a large part of the valley.
We probably had 27,000
to 30,000 troops,
15,000 horses, 37 elephants
all milling around in this place
for up to five days.
They would have devastated
this entire area.
Wouldn't be a blade
of grass left.
And so with that, you would
expect some evidence
to be found in the earth.
-Soil expert Randy Dirszowsky
is extracting soil cores
from deep in the ground
that are like timelines
from the earth.
-The material at the bottom
of the core is older.
It was deposited or developed
a long time ago.
But as you go up further,
you're getting material
that has accumulated
through time.
-Soil is made
of distinct layers,
appearing like stripes
in a soil core.
The layers are created when,
over the centuries,
organic matter like grass
decays, building up strata.
An enormous army passing through
would surely have left evidence
which can be found today.
-If anything were to happen
on the surface,
it would essentially
be recorded in that layer.
If there is a disturbance
of some kind,
you can likely recognize it.
♪♪
-If the team can find proof
Hannibal crossed the Alps
via the Col de la Traversette,
by far the highest
and most difficult route,
it will confirm he led his army
on an almost impossible journey.
But Carthage was a powerful
seafaring nation
well positioned in the heart
of the Mediterranean.
Why didn't Hannibal
simply go by sea?
-In 218 B.C., the Carthaginian
navy was weakened.
And the Romans
had the superior navy
in matter of number
of war boats.
They were able to obtain
big victories
on the Carthaginians.
Plus, they occupied Sicily,
Corsica, Sardinia,
which was an obstacle
for Hannibal,
who had not enough boats
to carry 90,000 men
to reach Italy.
-If Hannibal had been forced
to engage with Rome at sea,
he wouldn't have stood a chance.
And he would not
have been able to use
his most famous
and terrifying weapon --
the war elephants.
[ Elephants grunting ]
Tori Herridge, an expert
on ancient elephants,
wants to find out more about
the animals Hannibal used.
-The thought of Hannibal
bringing 37 elephants
over the Alps is ridiculous.
It seems completely impossible.
But he did it.
So the question becomes,
how did he do it, and why?
-Moving elephants across
treacherous mountains
seems extravagantly difficult.
Hannibal must have had a very
good reason to bring them along.
Military historian Mike Loades
has a copy of a relic
from the Carthaginian Empire
that suggests
Hannibal's motives.
-It's an exquisite coin,
and it dates
to Hannibal's period.
In fact, this is
Hannibal's father, Hamilcar.
And on the back,
we have an elephant.
-Wow.
-And the fact they've got it
on this coin tells us
that elephants were deeply
rooted in Carthaginian culture.
We cannot think of Hannibal
without the association
with elephants.
But actually, war elephants
weren't new with Hannibal.
-Well, kings of India were
using them for centuries
before they got to Carthage.
-Well, the Carthaginians were
actually quite late to the game.
-I mean, how do you think
he would have used
the elephants in battle?
-There's been debate.
Did they have war
elephants with a howdah?
That's that sort of wooden
castle construction on the back.
If you have that,
then you've got archers
and missile men
with javelins throwing down.
But if you haven't got that,
then the elephant is being used
as an intimidating
charging machine
to smash into the ranks
of the Romans.
-Single rider,
and the elephant itself
was the weapon.
-The coin might also tell us
about the nature
of Hannibal's elephants.
From ancient times and even
right up until the 20th century,
the Asian species was used
for most military operations.
But Tori has spotted
something unusual.
-What you can immediately see
from looking at it
is you've got an
African elephant on the back.
All the features are there,
the shape of that ear.
Not only is it really large,
but it's nice and rounded.
And look here, too. Look.
Can you see the back?
It's got this nice,
little dip in it.
That's the saddle on the back.
Shape of the spine
in an African elephant
has a sort of dip in it,
whereas an Asian elephant
kind of goes curved like that.
-Yes, yes, yes, yes.
-Today, African elephants
are only found
south of the Sahara Desert.
But historical records
don't mention Carthaginians
traveling so far to get them.
Where could Hannibal have found
native African elephants
closer to home?
-The Carthaginians seem
to get their elephants
from the Atlas Mountains.
But what we have now is
a situation in North Africa
where we've got
no elephants whatsoever.
You've only got
to go back 6,000 years,
well, actually a bit less,
before you get to a situation
where the Sahara wasn't quite
as inhospitable as it is now.
So it could be
that there is a kind of
a historical
population of elephants
that stretched all the way
up to the north coast.
And then as the Sahara
dried out,
from about 6,000
years ago onwards,
then you ended up with a remnant
population up in the north
that was
the Carthaginian elephants.
♪♪
-The team is in the Alps,
searching for remains
left by Hannibal's army.
-Almost.
-But this is not
their first field trip.
Back in 2015, they focused
their search in France
in a large, boggy area
below the Col de la Traversette
known as the French mire,
another location where Hannibal
might have rested his troops.
-Since I was certain that
we had the right route,
that was a place
to start looking.
-A mire is a type of wetland
unusual for mountain terrain.
Its grass and water
could have sustained an army.
Mires form when a lack of
oxygen, usually caused by water,
prevents organic material
from decaying fully,
preserving layers
of plant growth
and other matter.
If the team was going
to find evidence
of Hannibal's army anywhere,
it would be here.
They dug down and removed
sections of the ground
which they hoped would tell them
more about the route taken.
A layer of disturbed,
churned-up soil
is almost invisible
to the untrained eye.
-Well, actually, I didn't see
the churned-up layer
till we got back to Canada.
We would expect that
we would find horizontal beds.
This was the normal process.
And what stood out first
was at about 40 centimeters,
we had this massive,
churned-up bed.
-Between the layers
of regular soil
was one that
was strikingly different.
-How do we get
something like this?
Is it an earthquake?
It's possible.
But could you produce
a 15 centimeter layer?
I kind of doubt that.
I'd never seen
anything like that.
I mean,
this isn't what happened.
Something had to disturb it.
That was my thinking.
-Something in history,
something big,
moved through this mountain pass
and drastically altered
the ground.
The team hoped
it was Hannibal's army,
but further tests were needed.
-I'm a scientist --
I don't too excited
unless they run out of beer.
[ Laughs ]
Until I see the data, I'm pretty
skeptical about a lot of stuff.
So we went after the chemistry,
the mineralogy,
and you might say
the physical process
that went on
to churn that thing up.
-The first step
was chemical analysis,
and the results helped solve
one part of the puzzle.
The layer contained extremely
high levels of compounds
normally found in horse manure.
Bill enlisted the help of
microbiologist Chris Allen
to find out more.
Chris's challenge was to hunt
for remnants
of living organisms in the soil
that might provide proof
not of a few local animals
grazing in the Alps,
but of an army of horses.
-First thing to understand
is that in soil,
there are a lot of bacteria.
Now, let's imagine,
just over 2,000 years ago,
Hannibal comes through here
with his army,
and his horses start
defecating everywhere.
Now, there are
bacteria and feces.
And these bacteria are not
like bacteria in soil.
They live on different things.
And we can see that.
It stands out
very, very clearly.
-Chris analyzed
each layer in the soil cores,
cataloging all the bacteria
that had been present
in the ground
for the last 2,000 years,
and he found something unusual.
He came across ancient traces
of bacteria called Clostridia,
its remnants preserved
for centuries.
-The thing about Clostridia
is that it's found
in lots of different organisms,
lots of different environments.
But it's found at really, really
high levels in the horse gut
and in horse manure.
-Clostridia is normally
found in soil,
and it was present
in tiny amounts
in all the layers
Chris looked at.
But in the disturbed layer
of soil, it was abundant.
-If we go
to either older sediments
or younger sediments below that,
we see levels of Clostridia
that are what we'd expect
to normally find in soil,
so less than 1 percent.
But at this
particular point,
the Clostridia go to levels
that are way above 12 percent,
a massive increase.
It was an absolute
revelation for us.
-This unusually disrupted
layer of soil
revealed the presence
of an enormous number of horses.
-Well, I felt elated.
When I saw that, I thought,
you know,
this was beyond my belief
that we could capture
something that great.
-And carbon dating provided
even more evidence.
The soil was from
the same time period
Hannibal made his crossing --
roughly 2,200 years ago.
♪♪
-We have independent strands of
evidence telling us one thing,
that at this point in history,
there were a large group
of animals crossing the Alps
and that that group
of animals, we think,
were part of the army
that was led by Hannibal.
♪♪
-Bill's theory
that Hannibal crossed
over the Col de la Traversette
is now supported
by microbiological evidence.
But on its own,
that's not enough proof.
Polybius also mentioned
numerous physical features
found along the route,
giving Bill and historian
Eve MacDonald
almost a checklist
of elements to locate.
-People argue he took
several routes,
but this one stands
right out in my mind.
It has virtually all
of the environmental milestones
that Polybius mentioned.
-So when you were walking around
up there, you sort of could see
that this one talked
to you the most
about matching the sources,
perhaps.
-Absolutely.
-Bill believes the route
over the Col de la Traversette
contains all the main features
that Polybius wrote about --
the commanding view
of the Po River valley,
from the top of the mountain
where Hannibal addressed
his troops.
-He had only one source
of encouragement,
and that was the sight of Italy
clearly spread out below.
-This is an important piece
of evidence for us
because there is,
in fact, a clear view.
-A high, sheltered position
where the snow lay on the ground
year round.
-The fresh fall of this year's
snow had settled
on top of that
from the previous year,
which had remained frozen
since last winter.
-Currently, this is July,
and, you know,
here is last winter's snow
in the middle of summer.
-And a treacherously steep
downhill path.
-What Hannibal's men
actually found
was that the descent
was even more difficult.
-The track was narrow
and the descent precipitous.
If anyone strayed from the path
or lost his footing,
he fell from the heights
to certain death.
-But these features
can be found along
several of the proposed routes.
What Bill needs
is to find something unique.
-They reached a place
that was so narrow
that it was impossible
for the elephants
or the baggage animals
to move forward at all.
There had been a landslide,
and this had been made worse
by a second
and more recent landslip.
Confronted with this,
the army now became
thoroughly disheartened
and demoralized once more.
-Polybius writes about one of
the most difficult obstacles
the troops encountered --
a gia-This finally led meopped
the to test the Alpsks.
for the presence
of a two-tier rock fall
described by Polybius.
I figured this was a key thing.
If I found the rock fall,
I probably have the route.
-His soldiers might
have lost hope,
but Hannibal was determined
to get the men and animals
across.
But how did he handle
37 elephants?
♪♪
Cabárceno Park in Spain is home
to Europe's largest herd
of captive African elephants.
[ Elephant trumpets ]
Tori Herridge is meeting
chief vet
Santiago Borragan Santos,
who has studied
the herd for decades.
His expertise might shed light
on how Hannibal's men would
have controlled these giants.
Every morning, Santiago follows
a specific set of steps
to release the elephants
from their sleeping quarters.
-Oh, which one is this?
-This is Jumbo.
-Penny is always
the last elephant released.
-[ Speaking Spanish ]
-Here she comes.
-This is Penny.
-When she is finally let out,
the herd flocks to greet her.
-Oh, look, they're all coming.
-Uh-huh.
-Instinctively, elephants
follow the matriarch.
Penny coming out last limits
her authority over the herd.
She can no longer
lead the others
or trap them inside all day,
which has been known to happen.
-When they were
marching in an army,
you have to break the group
to have the human control.
-He's going to let us
know, I think.
-Yes.
-Hi, Penny.
-The only way
humans can control elephants
is to train each
animal individually.
But a war elephant takes
a long time to train.
Carthaginians might have
spent decades
preparing their elephants for
the noise and chaos of battle.
-[ Speaking Spanish ]
-They can get
this elephant here
to lift her foot up on command.
Well,
they've got some chains there,
which look really awful,
but they're just every so often
resting them on her legs
so that she can
get used to the feel
and the weight and the sound
and the experience of them,
so that if she ever needs
to be transported from here
to somewhere else,
they can secure her
in the van
that she'll move in.
They're using the gentlest
of methods here --
apples and pats
and instructions.
And even this has the effect of
some quite considerable control.
As far as Hannibal's
elephants are concerned,
I'm sure the techniques
weren't quite as gentle as this,
but I bet they were
really effective.
[ Elephants grunting ]
-But no matter how well-trained
the elephants were,
the climb over the rock fall
was difficult.
Deep in the Alps, the team has
been searching for the landslide
along Bill's proposed route.
This huge cascade of boulders
could be what
they're looking for.
-What Polybius is describing
in modern terms
is a slope failure of some kind.
This bulge that we see
beneath us
is the material
that would have come
from that rock fall
that Polybius was describing.
-And Polybius' writings
offer further proof
this is likely the landslide
Hannibal encountered.
-It's certain that the source
that Polybius is using
for this particular bit
must have been an eyewitness
because he's very, very specific
about the distance.
"A previous breaking away
of the hillside carried away
about one and a half stades
of the face of the mountain" --
about 300 meters.
-The 300 meters
is interesting
because that corresponds
almost exactly
to this path
that we're on now.
-But there's an even more
important detail
that might confirm
this is the landslide
that halted Hannibal.
-In Polybius and his histories,
he talked specifically
about the presence
of a two-stage rock fall,
two geologic events.
One, the oldest one,
bringing the slabs of rock
down onto the slope,
and a second one covering
part of that older unit.
-To determine
whether the landslide
is made up of rocks that fell
at two different moments
in time,
the team takes samples back
to the base to be analyzed.
♪♪
-What happens to the rocks is,
it will sit on the surface,
it will undergo
various interactions
with the atmosphere
and the biosphere.
Chemistries will change --
they will start to affect
the mineralogy
that's in the rock.
-When left exposed
on the mountain,
the rocks develop
weathering rinds --
layers of distinct color
on the surface.
The longer a rock is in
position, the thicker the rind.
-And essentially,
people usually use this
to give a relative
indication of time.
It's like a clock,
an imperfect one,
but a rough clock.
-Finding two thicknesses of rind
suggests the rock fall happened
in two stages.
-Those guys have
quite nice rinds.
-Mm.
-Well, you've got almost
2 millimeters on this lot,
Two, two and a half,
maybe three.
-And now the young one.
-Yeah.
But essentially, you've got
zero rind on the surface.
-So we've got an older group,
and we've got a younger group.
Perfect. That's perfect.
That fits the story exactly,
yeah.
-Bill and the team examined
more than a hundred rocks
from the landslide
and found that the rinds
on samples from one half
were on average
ten times thicker
than those from the other.
The team now has
conclusive proof
that these rocks broke away
at two different points in time.
Polybius' final clue
had at last been unlocked.
-I examined all the routes
multiple times,
and one of my objectives
always
was to look
for rock fall material.
The only col that carries
this prime example
is the Traversette.
All the others are free of this.
They have rock fall,
but an army of children
could walk through most of it.
♪♪
-Standing 10,000 feet high,
the Col de la Traversette
is the most unexpected route
because it is the most perilous.
For the army,
it would have seemed
like an impossible mission.
[ Wind whistling ]
[ Water rushing ]
Eve MacDonald has returned
to the South of France
to test out the route herself.
Her plan is to retrace
Hannibal's footsteps
at the same time of year
he made his march.
Thanks to an amazing piece
of astronomical evidence,
she knows exactly when that was.
-Polybius tells us
that it was in or around
the setting of
the constellation Pleiades
that Hannibal got
to the summit of the pass.
And if you look
up at the sky tonight,
you can see the moon is here
and you can also see
the Pleiades here,
quite low in the night sky.
-The setting of the Pleiades
occurs every year
in early November.
To ancient eyes, it was a signal
that snow would soon arrive
in the mountains.
-And so Hannibal
would have understood
that winter was coming
and he needed to get over
the Alps as soon as possible.
-The decision to cross the Alps
on the cusp of winter
seems like madness,
but Hannibal knew
what he was doing.
Hannibal had followed
the harvest season
across Europe,
and in autumn, the rivers
are at their lowest ebb.
-He started his march
in the late spring
and early summer
for weather conditions.
This was the best moment
for a big army
to cross the Pyrenees,
southern Gaul, and the Alps.
-Even in November, the weather
would have been mild
until they reached
the mountains.
Hannibal knew what
the conditions would be
because he had taken time
to find new allies.
-Such a big army
needed supplies on the way.
So contacts had been established
with the local tribes
to let him cross these regions,
to guide him, too,
and, at the same time,
to supply him the food needed
by such an army.
-But the Alps weren't the only
obstacle in Hannibal's path.
His first challenge was crossing
the mighty River Rhône.
Exactly where Hannibal crossed
the Rhône is unknown,
but clues from Polybius suggest
it was somewhere between
modern-day Beaucaire and Orange.
-Hannibal arrives
at the bank of the Rhône River
and realizes
the enormity of his task.
Today, it's cold and windy,
there's a mistral
blowing from the north,
and you get a real sense
of how rough
and how difficult
the crossing is gonna be.
-The Rhône is the largest
European river
emptying into the Mediterranean.
Its waters are wild
and unpredictable.
How Hannibal managed
to get his elephants
across the deadly currents
is a feat of both
engineering and biology.
-A pier of rafts lashed
two-by-two
was built into the water
and covered with earth.
A pair of rafts was lashed
to the end of the pier,
and the elephants
were walked onto the rafts,
which were then cut free
and towed across with boats.
Some elephants panicked
and fell off...
but were saved.
For owing to the power
and length of their trunks,
they kept them above the water
and breathed through them,
passing through the water
on their feet.
-Using their trunks
as snorkels
intrigues elephant expert
Tori Herridge.
-Swimming with a snorkel
is really difficult
if it's a long snorkel.
Our lungs can't cope
with the differences in pressure
between the air pressure
at the surface
and the pressure
our body's experiencing.
-Human lungs can't cope
with pressure changes
the way elephants' can
because they are surrounded by
a soft gap filled with fluid --
the pleural cavity.
But this cross-section
of an elephant's lung
shows a clear difference.
-On those lungs, there's no sign
of a cavity at all,
and that is unique
amongst mammals.
Elephants don't have
a pleural cavity.
Instead,
where that gap would be
is filled up
with connective tissue.
It allows them to breathe
underwater much more effectively
because it's much stronger,
denser tissue
that's resistant
to that kind of pressure.
So a description that's just
a tiny detail in Polybius
actually fits perfectly
with what we know
about both elephant behavior
and their internal anatomy.
♪♪
♪♪
-After crossing the Rhône,
Hannibal didn't take
the well-known route
along the Durance River
because there was a major
threat to the south
in nearby Marseille.
Eve and Tori are trying
to understand
the decisions that led him
to the Col de la Traversette.
-His intelligence tells him
that the Roman general,
Publius Scipio,
is at the city of Marseille.
-Ah.
-And the last thing
Hannibal wants to do
is engage with Roman armies.
He has to, if he's going
to succeed in his plan,
engage with the Romans in Italy.
-Can't go south
because of the Romans.
Only option, then,
is to head north.
-One of the most likely options
is the Drôme River Valley,
which comes off the Rhône
and heads up into the mountains
and then rejoins
the Durance river.
And there's a place on the way
where the path divides,
and at that place, he makes
an unexpected move.
♪♪
-At this pivotal fork
in Hannibal's route,
Eve and Tori team up with
mountain guide Damien Juhen.
Uncovering the next steps
in Hannibal's journey
requires some expert
local knowledge.
-Here, we are exactly
at the confluence
between the Durance River
on your left
and the Guil River
in front of you.
The Guil River is
going through the gorge,
really steep and narrow gorge,
the Guil Gorge,
and the Durance is going down
to the Mediterranean Sea.
-And that's the way
that Hannibal
would have come in, yeah?
-Yeah.
And at the fork, he had to make
a pretty critical decision.
He had to decide
whether to continue
up along the Durance River,
or he could veer off here
up the Guil River
and take the road
less traveled,
the road that no one
would have expected him to take,
and also the shorter route
into Italy.
-Why did he choose
the road less travelled?
-Because that's very much
his personality.
He was always somebody
who's into surprising the enemy.
♪♪
-But this decision
proved almost fatal.
Hannibal and his army
soon found themselves
at the bottom of a gorge
with wall after wall of sheer
rock towering over them.
-So, when Hannibal came
down into the valley,
you arrive,
and it's like a wall.
Okay?
And it's really impressive.
I mean, even for me,
the first time I came here,
it was -- I said,
"Where is -- Where is the road?"
So I think that for him,
it was really hard.
-How long would it take
to walk the gorge?
-Nearly a day.
It takes a long time
for these 20 K's of gorge.
-So for an army
laden down with animals,
in difficult conditions,
it would have been
more than one-day walk?
-Oh, for sure, yeah.
For sure, yes.
More than three days maybe.
-Slowly marching
through the gorge
put the troops
in a vulnerable position.
And local tribes
were only too eager
to take advantage of it.
-He runs into some locals
who pretend to be "friendly,"
so-called friendly guides,
but he's suspicious.
And two days into this march,
Polybius tells us
that these new friends
attacked the Carthaginians
as they were traversing
a certain difficult
and precipitous gorge.
-And this gorge here fits
that description quite well.
So just try to imagine,
all up above here,
Celtic tribesmen
hurling boulders,
rocks, projectiles,
anything they could find,
down on the soldiers
and the animals,
and picking them off one by one.
-The horses went mad with terror
at the wild shouts, which echoed
and re-echoed ever more loudly
from the forests
and mountainsides,
while chance blows and wounds
so panicked them
that they wrought havoc
among the men.
[ Horse neighs ]
-You can imagine the noise,
the chaos,
the animals turning around,
people dodging,
trying to take cover.
People are falling
into the river.
And there was no way for them
to defend themselves.
-The tribesmen took
whatever plunder they could.
♪♪
By the following day,
they were gone.
♪♪
Hannibal sustained huge losses,
his men and animals
scattered across the gorge.
The horses proved to be
a liability in the mountains,
and their panic
only made the attack worse.
But they were a crucial
military weapon
that Hannibal
could not do without.
Half of them belonged
to his elite mounted force.
-The Numidians were
light cavalry.
They came from North Africa.
They were lightly clad
and famously rode
without saddles
and even without bridles.
They used
just a simple neck rope.
that's all they had.
♪♪
-The Numidians were armed
with fistfuls of javelins,
riding at the enemy
and repeatedly
throwing their spears.
They were hit-and-run troops.
-Riding without a saddle?
Stirrups hadn't been invented.
Riding without a bit
and a bridle is challenging.
It's only possible
on a fantastically trained horse
like this.
-The fact that the Numidians
actually went into battle
like that is mind-blowing.
I can't imagine.
But they must have had
such control,
such a relationship
with their horses.
This horse should follow me.
Hup!
So without any tack,
without bridles and stirrups
and all of that sort of thing,
he's silent, it's stealthy.
It's the perfect horse
for scouting.
Imagine them in the Alps.
If you're going over
treacherous terrain,
you can get off,
and the horse will follow you.
-On Hannibal's journey,
the Numidian cavalry
were frequently sent ahead
to gather intelligence.
And they possessed
a special skill
that gave them
the element of surprise.
-They would lay
their horses down.
[ Clicks tongue ]
It's perfectly comfortable
for the horse.
There he goes.
There!
Look at that.
Now, just think how useful
that is if you're a scout.
You can get really low
behind the tall grasses
and scout the enemy's camp,
count their numbers.
Then they could simply get
on their horses.
[ Grunts ]
They were the eyes and ears
of Hannibal's invasion force.
[ Clicks tongue ]
Hah!
-But the horses weren't
the only animals
that had to endure
the long march
to the top of the mountain.
So, too, did Hannibal's
famous elephants.
At the Royal Veterinary College
in London,
Professor John Hutchinson has a
rather grisly piece of evidence
that reveals why elephants
are so well-suited
for long and hazardous journeys.
-Back foot.
-It is the left hind foot
of an adult Asian elephant.
-Donated to science by a zoo,
it shows that elephants,
surprisingly,
can be very good
mountain climbers.
-So you can see that
he's up on tip-toe --
that's really remarkable
about elephants.
So you can see the heel up here.
That would be the ankle joint.
And then the middle toe,
the third toe, going down here.
So the elephant's up on tip-toe.
-I love that, the fact that you
look at them from the outside
and they look so sort of
straight and flat-footed.
-Mm.
-But then you look inside them,
and it's a completely
different story.
-Yeah, it sure is.
And then look at what
we have here
on the back half of the foot.
There's this massive,
yellowish, white tissue.
It's all fat pad.
Just like our heel pad
on our foot, but massive.
-When you imagine an elephant
moving through
the mountainous areas,
they might have been better off
than something with a hoof.
-Yeah.
Elephants have a foot that
is able to change its shape
to suit the environment.
-But it's not just
the structure of the foot
that makes elephants
well-adapted
for Hannibal's mission.
They are also very efficient
when in motion.
-As we see in this video,
the limbs are really straight
when they're supporting the body
and walking,
so they're like pillars.
The elephant
only flexes its joints
mainly when the feet
are off the ground,
so the muscles don't have
to exert as much force
to support an elephant's weight.
-Perfect for
long-distance travel.
-It is. They have a really
flexible way of moving.
And very steep slopes,
they'll get down
on their knees,
basically, and crawl along
to get up high slopes.
They have that kind of stability
and economy
that is uniquely elephant.
[ Bird cries ]
♪♪
-And there's proof that
elephants can cross the Alps...
-[ Laughs ] Crazy.
-...thanks to an
extraordinary experiment
conducted almost 60 years ago.
-Wow.
Actually, Jumbo looks larger
than I was remembering.
-In the summer of 1959,
British engineer John Hoyte
led a team of scientists
and explorers
on one of the most ambitious
experimental archaeology events
ever attempted --
taking an elephant over the Alps
in Hannibal's footsteps.
Sir Richard Jolly
was second in command.
-The scientific part
of our expedition
was a very careful checking
of Jumbo's speed
along the level
and when ascending
towards the summit
and as high
as 2,083 meters.
We were seeing whether
the difference in altitude
and the climbing challenge
slowed Jumbo down in any way.
And the short answer was
no, it didn't.
I think the elephants, they're
very sensitive creatures,
and if well-trained,
very confident
and in control of themselves.
[ Laughs ]
Yeah, and there's Jumbo
having some fun.
Good, old Jumbo.
Hmm.
-So elephants, despite living
in warmer climates,
can endure the cold and
alpine terrain in short bursts.
[ Elephant trumpets ]
With winter approaching
and the troops delayed,
Hannibal needed
to speed up the march,
so he loaded his
pack animals with rations.
Even the humble donkey
was essential.
Tori and Eve are attempting
the final leg
of Hannibal's climb into Italy,
going up to
the Col de la Traversette
and testing out how
the army would have coped.
-If you're on a mission
to be as quick,
moving as fast
and as light as possible,
then you're gonna always
have to trade-off
between what you carry
and what you collect.
And so the more you carry,
the less time you've got
to spend foraging.
-And once he starts to go
up to the mountains,
he's gonna have to be carrying
an awful lot of food
because there really isn't
much capacity up here to forage.
-The donkeys would have carried
about 220 pounds worth of hay,
enough food to feed
one horse for 20 days.
However,
Hannibal had 9,000 horses
and 37 voracious elephants.
Using historical records,
scholars have estimated
how much food the troops
and pack animals needed.
But for the elephants,
it's not clear.
-Mm-hmm.
Mm-hmm.
-And they also eat the grass
outside, of course.
-Si.
-Elephants are big,
hungry beasts.
An adult elephant can consume
up to 300 pounds of food
in a single day
and a lot more
if constantly on the march.
[ Bird cries ]
As they pushed on toward
the Col de la Traversette,
Hannibal's exhausted army
would have been spread
across 20 miles
of the mountain range.
The ancient texts state that
in these barren mountains,
the food supplies ran out.
♪♪
-The animals were nearly dead
from starvation,
since the high passes
were almost
totally devoid of vegetation,
and whatever fodder
there might have been
was buried under snow.
-Something
had clearly gone wrong
in Hannibal's planning.
-We're gonna stop there
just a second.
-The team encounters a problem
that Hannibal himself must
have faced in early November.
-Now we are up to 2,500
meters elevation,
and the path become
really, really hard, difficult
because it's steep
and really icy
and with the donkey,
we can't, go through.
For us, it can be okay,
but with donkeys,
it's impossible, for sure.
-And then you get
something like this,
and there's no way
you'd get a beast up there.
They'd have to go ahead
and hack the ice off.
And even then, you can
imagine the situation
where something lost
its footing and just slid.
-We have so many tales of it.
And it's amazing that two
or three times
we get this sense of these
pack animals knocking people
and themselves and other horses
and everything off the pass.
-Many pack animals must have
died on these steep, icy slopes.
Losing any of them
would have been a real concern
for an army wholly dependent
on the food they carried.
-As you lose your pack animals,
like, it's not just the beast
that's dead.
It's, you know, that's --
that's, 100 kilograms of load
that you can no longer
take with you.
That's 20 days of horse feed.
-And that's what
Polybius says
is, by the time they get
over the other side
to anywhere that's good grazing,
the animals are starving.
-Hmm.
-So, I mean, that's it.
They've lost so much
of their supplies
just coming up the sort of
dangerous routes like this.
♪♪
-The army marched for
nine days in the Alps,
camping in the freezing cold,
moving night and day.
♪♪
At long last,
after a desolate climb,
Hannibal reached
the Col de la Traversette.
From high atop the mountain,
the view of Italy
and the prospect of conquest
stretched out before him.
-Here we are,
France on one side,
Italy on the other,
standing on the border.
-His army must be spread out
all down the valley.
It takes two days
for everybody to come --
30,000 men
and maybe 10,000 pack animals,
and, of course, 37 elephants.
♪♪
-Hannibal needs
to make them believe
that they can do
what they set out to do.
And he encourages his army
with stories
of all the riches
and the wealth to be won
and of all the heroic adventures
that lie ahead of them.
-The monumental Alps, with their
snowy spires and craggy slopes,
met their match.
Now, for the first time,
scientific evidence
is confirming
the historic event --
that Hannibal crossed
these mountains at the highest
and most difficult pass
of them all,
the Col de la Traversette.
-Finally,
we are pulling together
some scientific evidence
that this is the route
that he took across the Alps.
And who would have expected
that this could be
coming down to something
as simple and tiny
as the bacteria
hidden in the soil?
-We finally had narrowed
the pass down to one place.
-A journey that became legendary
has now been made real.
-Whilst it was difficult,
whilst it would
have been bloody,
there would have been deaths
of both people and of animals,
at each stage,
I don't think any of those
problems were insurmountable.
If you're willing to push,
then why not?
You could do it.
-Hannibal's invasion of Rome
over the Alps
sent shock waves
through the ancient world.
By the end of the year,
he had won two decisive
battles on Roman soil.
Carthage was safe for now.
For 15 long years,
he waged a campaign of
annihilation throughout Italy.
But eventually,
Rome stood strong once more,
and the tide of victory turned.
Hannibal was finally
defeated on home soil,
and Carthage was left in ruins.
But 2,000 years later,
his incredible journey
over the Alps
stands as a testament
to his unflinching determination
and military genius.
-This was undoubtedly
the most difficult pass
Hannibal could have taken.
And we sort of have
to ask ourselves,
why did he take
the hardest route?
And what probably drove
that decision
lay in what made
the man who he was.
Because the more
difficult the journey,
the more difficult
his quest almost,
the greater his
heroic status would be.
2,200 years later,
we're still absolutely
fascinated by Hannibal
and especially by this journey
he made over the Alps.
-He created the myth,
and we still believe it.
-Hannibal's journey
was legendary,
and now we know
it wasn't a myth.
♪♪
-218 B.C. -- a young general
leads a vast army across Europe
in a surprise attack
on the Roman Republic.
In his path lies an almost
impossible challenge --
the foreboding Alps.
-When they arrived
at the mountains
and they began to climb,
the full enormity
of the task ahead
sunk into the soldiers.
The ancient writers talk about
the way that the soldiers
considered these mountains
to be almost supernatural.
♪♪
-It is only their belief
in their daring commander
that keeps them going.
That man is the legend
of Carthage -- Hannibal Barca.
And that winter, he embarked
on one of the most audacious
military feats in history --
the crossing
of the French Alps into Italy
with a force of almost
40,000 soldiers,
9,000 cavalry,
and, perhaps most famous of all,
37 elephants.
-I just find it
so improbable
elephants passing through here.
-But no one has ever found
a single piece
of physical evidence
marking Hannibal's exact route.
Now, an international team
of scientists and historians
are determined to uncover where
Hannibal made his epic march.
-It was an absolute
revelation for us.
-I felt elated.
I'd never seen
anything like that.
I mean, this isn't what happens.
-And they will recreate
the journey...
-Stop there.
It's really icy.
I don't think we can go there.
We have to find another way.
-...to discover how
Hannibal conquered
the fearsome mountains.
"Hannibal in the Alps."
♪♪
[ Wind blowing ]
-The Alps.
80,000 square miles
of desolate,
hostile mountain terrain.
And not a trace
of the extraordinary events
that took place here
over 2,000 years ago.
Hannibal's exact route has
remained an enduring mystery.
♪♪
As the turn of the first
millennium approached,
the two superpowers
of Carthage in North Africa
and the Roman Republic
were preparing for war.
Fearing a Roman invasion
of Carthage,
Hannibal drew up plans
for a daring surprise attack.
Instead of launching
an invasion by sea,
he would lead an army
across the French Alps,
sweep through Italy,
and take on the might of Rome.
Historian Eve MacDonald
has spent her career
following the trail of Hannibal,
fascinated by the man himself.
-Getting inside the minds of
people who lived 2,000 years ago
is so difficult.
Even in Roman times,
just after the events,
there was controversy
over which pass
Hannibal took over the Alps.
-What is known about his path
comes from ancient writers
who recorded the events
two millennia ago.
-Polybius is our best source
by a long way.
Polybius wrote about 60 years
after Hannibal crossed the Alps.
Now, he had access
to eyewitnesses
who were with Hannibal.
And that is why he's probably
our most valuable source.
-In his account of Hannibal's
crossing of the Alps,
Polybius mentions numerous
geographical features
encountered along the route.
-The sight of Italy
clearly spread out below.
The fresh fall
of this year's snow.
A landslide made worse
by a second
and more recent landslip.
-We can use these texts
almost as guides
to go into the mountains
and try and piece together
an accurate account
of the route which he took.
-Eve is joining
geologist Bill Mahaney
to find where Hannibal actually
went across the mountains.
-I'm a mountaineer.
In the old days,
I went climbing.
Later days, I did geology.
That's what I do.
-Bill is convinced
the mountains
must hold the key.
His team is searching
for microscopic clues
buried beneath the surface...
-It's a good one.
-Got 50 centimeters of different
environmental change.
Fantastic.
-Bill does not believe
an enormous army
could have moved
through the mountains
without leaving
something behind,
and he is determined to find it.
For him, discovering the truth
about Hannibal's
mountain crossing
is a lifelong obsession.
-He was a mountain man.
He tackled a mountain
experience that
absolutely floors me.
I've been in the mountains
with 100, 150 people.
It's pandemonium.
People fall in crevasses,
people get lost off snowmobiles,
people get killed.
It's crazy.
And he took 30,000 men,
37 elephants,
and God knows how many horses
across one of the imposing
mountains in the world.
You have to admit
this man was --
he knew what he was doing,
and he was a man of some genius
to be able to pull it off.
♪♪
-Hannibal came from a family
of generals and statesmen
and he was raised to see Rome
as a mortal enemy.
Historian Nejib Ben Lazreg
is from Tunisia,
the same area as Carthage,
where Hannibal's legacy
is still very much alive.
-Hannibal was brought up
in a family of
military figures
like his father Hamilcar Barca,
who defeated the Romans
in big battles in Sicily,
and the mercenaries in Africa
when they rebelled
against Carthage.
-Inheriting his father's
strategic brilliance,
Hannibal gave Carthage
its most glorious hour.
-He was a very skilled man.
And he had the ability to spot
the good place where he could
trap the enemy.
I consider that he is the
greatest figure in our history.
[ Wind howling ]
-No one knows
Hannibal's exact path,
but based on Polybius
and other ancient guides,
four main routes across
the Alps are possible --
two northern routes over
the Col du Mont Cenis
or the Col de Clapier --
one running through the center
and over
the Col de Montgenèvre
and a southern route--
the highest and most dangerous
of all --
over the Col de la Traversette.
And Bill believes
it's this southern pass
Hannibal used to march his army
into enemy territory.
It's a route so treacherous
that most historians
have dismissed it as impossible.
But Bill wants to prove
the historians wrong.
-I mean, if that is
the Hannibal layer,
that's perfect.
-Polybius tells us that Hannibal
rested his army for a few days
at key points along the route.
The team hopes the troops
stayed long enough
to have left their mark
on the land.
-They established a resting camp
for two days
that gave the soldiers
a breathing space
in which to recover.
-Bill believes
this open area below the pass
could be
one of those resting places.
-Just imagine the troops
moving down through here
would have basically covered
a large part of the valley.
We probably had 27,000
to 30,000 troops,
15,000 horses, 37 elephants
all milling around in this place
for up to five days.
They would have devastated
this entire area.
Wouldn't be a blade
of grass left.
And so with that, you would
expect some evidence
to be found in the earth.
-Soil expert Randy Dirszowsky
is extracting soil cores
from deep in the ground
that are like timelines
from the earth.
-The material at the bottom
of the core is older.
It was deposited or developed
a long time ago.
But as you go up further,
you're getting material
that has accumulated
through time.
-Soil is made
of distinct layers,
appearing like stripes
in a soil core.
The layers are created when,
over the centuries,
organic matter like grass
decays, building up strata.
An enormous army passing through
would surely have left evidence
which can be found today.
-If anything were to happen
on the surface,
it would essentially
be recorded in that layer.
If there is a disturbance
of some kind,
you can likely recognize it.
♪♪
-If the team can find proof
Hannibal crossed the Alps
via the Col de la Traversette,
by far the highest
and most difficult route,
it will confirm he led his army
on an almost impossible journey.
But Carthage was a powerful
seafaring nation
well positioned in the heart
of the Mediterranean.
Why didn't Hannibal
simply go by sea?
-In 218 B.C., the Carthaginian
navy was weakened.
And the Romans
had the superior navy
in matter of number
of war boats.
They were able to obtain
big victories
on the Carthaginians.
Plus, they occupied Sicily,
Corsica, Sardinia,
which was an obstacle
for Hannibal,
who had not enough boats
to carry 90,000 men
to reach Italy.
-If Hannibal had been forced
to engage with Rome at sea,
he wouldn't have stood a chance.
And he would not
have been able to use
his most famous
and terrifying weapon --
the war elephants.
[ Elephants grunting ]
Tori Herridge, an expert
on ancient elephants,
wants to find out more about
the animals Hannibal used.
-The thought of Hannibal
bringing 37 elephants
over the Alps is ridiculous.
It seems completely impossible.
But he did it.
So the question becomes,
how did he do it, and why?
-Moving elephants across
treacherous mountains
seems extravagantly difficult.
Hannibal must have had a very
good reason to bring them along.
Military historian Mike Loades
has a copy of a relic
from the Carthaginian Empire
that suggests
Hannibal's motives.
-It's an exquisite coin,
and it dates
to Hannibal's period.
In fact, this is
Hannibal's father, Hamilcar.
And on the back,
we have an elephant.
-Wow.
-And the fact they've got it
on this coin tells us
that elephants were deeply
rooted in Carthaginian culture.
We cannot think of Hannibal
without the association
with elephants.
But actually, war elephants
weren't new with Hannibal.
-Well, kings of India were
using them for centuries
before they got to Carthage.
-Well, the Carthaginians were
actually quite late to the game.
-I mean, how do you think
he would have used
the elephants in battle?
-There's been debate.
Did they have war
elephants with a howdah?
That's that sort of wooden
castle construction on the back.
If you have that,
then you've got archers
and missile men
with javelins throwing down.
But if you haven't got that,
then the elephant is being used
as an intimidating
charging machine
to smash into the ranks
of the Romans.
-Single rider,
and the elephant itself
was the weapon.
-The coin might also tell us
about the nature
of Hannibal's elephants.
From ancient times and even
right up until the 20th century,
the Asian species was used
for most military operations.
But Tori has spotted
something unusual.
-What you can immediately see
from looking at it
is you've got an
African elephant on the back.
All the features are there,
the shape of that ear.
Not only is it really large,
but it's nice and rounded.
And look here, too. Look.
Can you see the back?
It's got this nice,
little dip in it.
That's the saddle on the back.
Shape of the spine
in an African elephant
has a sort of dip in it,
whereas an Asian elephant
kind of goes curved like that.
-Yes, yes, yes, yes.
-Today, African elephants
are only found
south of the Sahara Desert.
But historical records
don't mention Carthaginians
traveling so far to get them.
Where could Hannibal have found
native African elephants
closer to home?
-The Carthaginians seem
to get their elephants
from the Atlas Mountains.
But what we have now is
a situation in North Africa
where we've got
no elephants whatsoever.
You've only got
to go back 6,000 years,
well, actually a bit less,
before you get to a situation
where the Sahara wasn't quite
as inhospitable as it is now.
So it could be
that there is a kind of
a historical
population of elephants
that stretched all the way
up to the north coast.
And then as the Sahara
dried out,
from about 6,000
years ago onwards,
then you ended up with a remnant
population up in the north
that was
the Carthaginian elephants.
♪♪
-The team is in the Alps,
searching for remains
left by Hannibal's army.
-Almost.
-But this is not
their first field trip.
Back in 2015, they focused
their search in France
in a large, boggy area
below the Col de la Traversette
known as the French mire,
another location where Hannibal
might have rested his troops.
-Since I was certain that
we had the right route,
that was a place
to start looking.
-A mire is a type of wetland
unusual for mountain terrain.
Its grass and water
could have sustained an army.
Mires form when a lack of
oxygen, usually caused by water,
prevents organic material
from decaying fully,
preserving layers
of plant growth
and other matter.
If the team was going
to find evidence
of Hannibal's army anywhere,
it would be here.
They dug down and removed
sections of the ground
which they hoped would tell them
more about the route taken.
A layer of disturbed,
churned-up soil
is almost invisible
to the untrained eye.
-Well, actually, I didn't see
the churned-up layer
till we got back to Canada.
We would expect that
we would find horizontal beds.
This was the normal process.
And what stood out first
was at about 40 centimeters,
we had this massive,
churned-up bed.
-Between the layers
of regular soil
was one that
was strikingly different.
-How do we get
something like this?
Is it an earthquake?
It's possible.
But could you produce
a 15 centimeter layer?
I kind of doubt that.
I'd never seen
anything like that.
I mean,
this isn't what happened.
Something had to disturb it.
That was my thinking.
-Something in history,
something big,
moved through this mountain pass
and drastically altered
the ground.
The team hoped
it was Hannibal's army,
but further tests were needed.
-I'm a scientist --
I don't too excited
unless they run out of beer.
[ Laughs ]
Until I see the data, I'm pretty
skeptical about a lot of stuff.
So we went after the chemistry,
the mineralogy,
and you might say
the physical process
that went on
to churn that thing up.
-The first step
was chemical analysis,
and the results helped solve
one part of the puzzle.
The layer contained extremely
high levels of compounds
normally found in horse manure.
Bill enlisted the help of
microbiologist Chris Allen
to find out more.
Chris's challenge was to hunt
for remnants
of living organisms in the soil
that might provide proof
not of a few local animals
grazing in the Alps,
but of an army of horses.
-First thing to understand
is that in soil,
there are a lot of bacteria.
Now, let's imagine,
just over 2,000 years ago,
Hannibal comes through here
with his army,
and his horses start
defecating everywhere.
Now, there are
bacteria and feces.
And these bacteria are not
like bacteria in soil.
They live on different things.
And we can see that.
It stands out
very, very clearly.
-Chris analyzed
each layer in the soil cores,
cataloging all the bacteria
that had been present
in the ground
for the last 2,000 years,
and he found something unusual.
He came across ancient traces
of bacteria called Clostridia,
its remnants preserved
for centuries.
-The thing about Clostridia
is that it's found
in lots of different organisms,
lots of different environments.
But it's found at really, really
high levels in the horse gut
and in horse manure.
-Clostridia is normally
found in soil,
and it was present
in tiny amounts
in all the layers
Chris looked at.
But in the disturbed layer
of soil, it was abundant.
-If we go
to either older sediments
or younger sediments below that,
we see levels of Clostridia
that are what we'd expect
to normally find in soil,
so less than 1 percent.
But at this
particular point,
the Clostridia go to levels
that are way above 12 percent,
a massive increase.
It was an absolute
revelation for us.
-This unusually disrupted
layer of soil
revealed the presence
of an enormous number of horses.
-Well, I felt elated.
When I saw that, I thought,
you know,
this was beyond my belief
that we could capture
something that great.
-And carbon dating provided
even more evidence.
The soil was from
the same time period
Hannibal made his crossing --
roughly 2,200 years ago.
♪♪
-We have independent strands of
evidence telling us one thing,
that at this point in history,
there were a large group
of animals crossing the Alps
and that that group
of animals, we think,
were part of the army
that was led by Hannibal.
♪♪
-Bill's theory
that Hannibal crossed
over the Col de la Traversette
is now supported
by microbiological evidence.
But on its own,
that's not enough proof.
Polybius also mentioned
numerous physical features
found along the route,
giving Bill and historian
Eve MacDonald
almost a checklist
of elements to locate.
-People argue he took
several routes,
but this one stands
right out in my mind.
It has virtually all
of the environmental milestones
that Polybius mentioned.
-So when you were walking around
up there, you sort of could see
that this one talked
to you the most
about matching the sources,
perhaps.
-Absolutely.
-Bill believes the route
over the Col de la Traversette
contains all the main features
that Polybius wrote about --
the commanding view
of the Po River valley,
from the top of the mountain
where Hannibal addressed
his troops.
-He had only one source
of encouragement,
and that was the sight of Italy
clearly spread out below.
-This is an important piece
of evidence for us
because there is,
in fact, a clear view.
-A high, sheltered position
where the snow lay on the ground
year round.
-The fresh fall of this year's
snow had settled
on top of that
from the previous year,
which had remained frozen
since last winter.
-Currently, this is July,
and, you know,
here is last winter's snow
in the middle of summer.
-And a treacherously steep
downhill path.
-What Hannibal's men
actually found
was that the descent
was even more difficult.
-The track was narrow
and the descent precipitous.
If anyone strayed from the path
or lost his footing,
he fell from the heights
to certain death.
-But these features
can be found along
several of the proposed routes.
What Bill needs
is to find something unique.
-They reached a place
that was so narrow
that it was impossible
for the elephants
or the baggage animals
to move forward at all.
There had been a landslide,
and this had been made worse
by a second
and more recent landslip.
Confronted with this,
the army now became
thoroughly disheartened
and demoralized once more.
-Polybius writes about one of
the most difficult obstacles
the troops encountered --
a gia-This finally led meopped
the to test the Alpsks.
for the presence
of a two-tier rock fall
described by Polybius.
I figured this was a key thing.
If I found the rock fall,
I probably have the route.
-His soldiers might
have lost hope,
but Hannibal was determined
to get the men and animals
across.
But how did he handle
37 elephants?
♪♪
Cabárceno Park in Spain is home
to Europe's largest herd
of captive African elephants.
[ Elephant trumpets ]
Tori Herridge is meeting
chief vet
Santiago Borragan Santos,
who has studied
the herd for decades.
His expertise might shed light
on how Hannibal's men would
have controlled these giants.
Every morning, Santiago follows
a specific set of steps
to release the elephants
from their sleeping quarters.
-Oh, which one is this?
-This is Jumbo.
-Penny is always
the last elephant released.
-[ Speaking Spanish ]
-Here she comes.
-This is Penny.
-When she is finally let out,
the herd flocks to greet her.
-Oh, look, they're all coming.
-Uh-huh.
-Instinctively, elephants
follow the matriarch.
Penny coming out last limits
her authority over the herd.
She can no longer
lead the others
or trap them inside all day,
which has been known to happen.
-When they were
marching in an army,
you have to break the group
to have the human control.
-He's going to let us
know, I think.
-Yes.
-Hi, Penny.
-The only way
humans can control elephants
is to train each
animal individually.
But a war elephant takes
a long time to train.
Carthaginians might have
spent decades
preparing their elephants for
the noise and chaos of battle.
-[ Speaking Spanish ]
-They can get
this elephant here
to lift her foot up on command.
Well,
they've got some chains there,
which look really awful,
but they're just every so often
resting them on her legs
so that she can
get used to the feel
and the weight and the sound
and the experience of them,
so that if she ever needs
to be transported from here
to somewhere else,
they can secure her
in the van
that she'll move in.
They're using the gentlest
of methods here --
apples and pats
and instructions.
And even this has the effect of
some quite considerable control.
As far as Hannibal's
elephants are concerned,
I'm sure the techniques
weren't quite as gentle as this,
but I bet they were
really effective.
[ Elephants grunting ]
-But no matter how well-trained
the elephants were,
the climb over the rock fall
was difficult.
Deep in the Alps, the team has
been searching for the landslide
along Bill's proposed route.
This huge cascade of boulders
could be what
they're looking for.
-What Polybius is describing
in modern terms
is a slope failure of some kind.
This bulge that we see
beneath us
is the material
that would have come
from that rock fall
that Polybius was describing.
-And Polybius' writings
offer further proof
this is likely the landslide
Hannibal encountered.
-It's certain that the source
that Polybius is using
for this particular bit
must have been an eyewitness
because he's very, very specific
about the distance.
"A previous breaking away
of the hillside carried away
about one and a half stades
of the face of the mountain" --
about 300 meters.
-The 300 meters
is interesting
because that corresponds
almost exactly
to this path
that we're on now.
-But there's an even more
important detail
that might confirm
this is the landslide
that halted Hannibal.
-In Polybius and his histories,
he talked specifically
about the presence
of a two-stage rock fall,
two geologic events.
One, the oldest one,
bringing the slabs of rock
down onto the slope,
and a second one covering
part of that older unit.
-To determine
whether the landslide
is made up of rocks that fell
at two different moments
in time,
the team takes samples back
to the base to be analyzed.
♪♪
-What happens to the rocks is,
it will sit on the surface,
it will undergo
various interactions
with the atmosphere
and the biosphere.
Chemistries will change --
they will start to affect
the mineralogy
that's in the rock.
-When left exposed
on the mountain,
the rocks develop
weathering rinds --
layers of distinct color
on the surface.
The longer a rock is in
position, the thicker the rind.
-And essentially,
people usually use this
to give a relative
indication of time.
It's like a clock,
an imperfect one,
but a rough clock.
-Finding two thicknesses of rind
suggests the rock fall happened
in two stages.
-Those guys have
quite nice rinds.
-Mm.
-Well, you've got almost
2 millimeters on this lot,
Two, two and a half,
maybe three.
-And now the young one.
-Yeah.
But essentially, you've got
zero rind on the surface.
-So we've got an older group,
and we've got a younger group.
Perfect. That's perfect.
That fits the story exactly,
yeah.
-Bill and the team examined
more than a hundred rocks
from the landslide
and found that the rinds
on samples from one half
were on average
ten times thicker
than those from the other.
The team now has
conclusive proof
that these rocks broke away
at two different points in time.
Polybius' final clue
had at last been unlocked.
-I examined all the routes
multiple times,
and one of my objectives
always
was to look
for rock fall material.
The only col that carries
this prime example
is the Traversette.
All the others are free of this.
They have rock fall,
but an army of children
could walk through most of it.
♪♪
-Standing 10,000 feet high,
the Col de la Traversette
is the most unexpected route
because it is the most perilous.
For the army,
it would have seemed
like an impossible mission.
[ Wind whistling ]
[ Water rushing ]
Eve MacDonald has returned
to the South of France
to test out the route herself.
Her plan is to retrace
Hannibal's footsteps
at the same time of year
he made his march.
Thanks to an amazing piece
of astronomical evidence,
she knows exactly when that was.
-Polybius tells us
that it was in or around
the setting of
the constellation Pleiades
that Hannibal got
to the summit of the pass.
And if you look
up at the sky tonight,
you can see the moon is here
and you can also see
the Pleiades here,
quite low in the night sky.
-The setting of the Pleiades
occurs every year
in early November.
To ancient eyes, it was a signal
that snow would soon arrive
in the mountains.
-And so Hannibal
would have understood
that winter was coming
and he needed to get over
the Alps as soon as possible.
-The decision to cross the Alps
on the cusp of winter
seems like madness,
but Hannibal knew
what he was doing.
Hannibal had followed
the harvest season
across Europe,
and in autumn, the rivers
are at their lowest ebb.
-He started his march
in the late spring
and early summer
for weather conditions.
This was the best moment
for a big army
to cross the Pyrenees,
southern Gaul, and the Alps.
-Even in November, the weather
would have been mild
until they reached
the mountains.
Hannibal knew what
the conditions would be
because he had taken time
to find new allies.
-Such a big army
needed supplies on the way.
So contacts had been established
with the local tribes
to let him cross these regions,
to guide him, too,
and, at the same time,
to supply him the food needed
by such an army.
-But the Alps weren't the only
obstacle in Hannibal's path.
His first challenge was crossing
the mighty River Rhône.
Exactly where Hannibal crossed
the Rhône is unknown,
but clues from Polybius suggest
it was somewhere between
modern-day Beaucaire and Orange.
-Hannibal arrives
at the bank of the Rhône River
and realizes
the enormity of his task.
Today, it's cold and windy,
there's a mistral
blowing from the north,
and you get a real sense
of how rough
and how difficult
the crossing is gonna be.
-The Rhône is the largest
European river
emptying into the Mediterranean.
Its waters are wild
and unpredictable.
How Hannibal managed
to get his elephants
across the deadly currents
is a feat of both
engineering and biology.
-A pier of rafts lashed
two-by-two
was built into the water
and covered with earth.
A pair of rafts was lashed
to the end of the pier,
and the elephants
were walked onto the rafts,
which were then cut free
and towed across with boats.
Some elephants panicked
and fell off...
but were saved.
For owing to the power
and length of their trunks,
they kept them above the water
and breathed through them,
passing through the water
on their feet.
-Using their trunks
as snorkels
intrigues elephant expert
Tori Herridge.
-Swimming with a snorkel
is really difficult
if it's a long snorkel.
Our lungs can't cope
with the differences in pressure
between the air pressure
at the surface
and the pressure
our body's experiencing.
-Human lungs can't cope
with pressure changes
the way elephants' can
because they are surrounded by
a soft gap filled with fluid --
the pleural cavity.
But this cross-section
of an elephant's lung
shows a clear difference.
-On those lungs, there's no sign
of a cavity at all,
and that is unique
amongst mammals.
Elephants don't have
a pleural cavity.
Instead,
where that gap would be
is filled up
with connective tissue.
It allows them to breathe
underwater much more effectively
because it's much stronger,
denser tissue
that's resistant
to that kind of pressure.
So a description that's just
a tiny detail in Polybius
actually fits perfectly
with what we know
about both elephant behavior
and their internal anatomy.
♪♪
♪♪
-After crossing the Rhône,
Hannibal didn't take
the well-known route
along the Durance River
because there was a major
threat to the south
in nearby Marseille.
Eve and Tori are trying
to understand
the decisions that led him
to the Col de la Traversette.
-His intelligence tells him
that the Roman general,
Publius Scipio,
is at the city of Marseille.
-Ah.
-And the last thing
Hannibal wants to do
is engage with Roman armies.
He has to, if he's going
to succeed in his plan,
engage with the Romans in Italy.
-Can't go south
because of the Romans.
Only option, then,
is to head north.
-One of the most likely options
is the Drôme River Valley,
which comes off the Rhône
and heads up into the mountains
and then rejoins
the Durance river.
And there's a place on the way
where the path divides,
and at that place, he makes
an unexpected move.
♪♪
-At this pivotal fork
in Hannibal's route,
Eve and Tori team up with
mountain guide Damien Juhen.
Uncovering the next steps
in Hannibal's journey
requires some expert
local knowledge.
-Here, we are exactly
at the confluence
between the Durance River
on your left
and the Guil River
in front of you.
The Guil River is
going through the gorge,
really steep and narrow gorge,
the Guil Gorge,
and the Durance is going down
to the Mediterranean Sea.
-And that's the way
that Hannibal
would have come in, yeah?
-Yeah.
And at the fork, he had to make
a pretty critical decision.
He had to decide
whether to continue
up along the Durance River,
or he could veer off here
up the Guil River
and take the road
less traveled,
the road that no one
would have expected him to take,
and also the shorter route
into Italy.
-Why did he choose
the road less travelled?
-Because that's very much
his personality.
He was always somebody
who's into surprising the enemy.
♪♪
-But this decision
proved almost fatal.
Hannibal and his army
soon found themselves
at the bottom of a gorge
with wall after wall of sheer
rock towering over them.
-So, when Hannibal came
down into the valley,
you arrive,
and it's like a wall.
Okay?
And it's really impressive.
I mean, even for me,
the first time I came here,
it was -- I said,
"Where is -- Where is the road?"
So I think that for him,
it was really hard.
-How long would it take
to walk the gorge?
-Nearly a day.
It takes a long time
for these 20 K's of gorge.
-So for an army
laden down with animals,
in difficult conditions,
it would have been
more than one-day walk?
-Oh, for sure, yeah.
For sure, yes.
More than three days maybe.
-Slowly marching
through the gorge
put the troops
in a vulnerable position.
And local tribes
were only too eager
to take advantage of it.
-He runs into some locals
who pretend to be "friendly,"
so-called friendly guides,
but he's suspicious.
And two days into this march,
Polybius tells us
that these new friends
attacked the Carthaginians
as they were traversing
a certain difficult
and precipitous gorge.
-And this gorge here fits
that description quite well.
So just try to imagine,
all up above here,
Celtic tribesmen
hurling boulders,
rocks, projectiles,
anything they could find,
down on the soldiers
and the animals,
and picking them off one by one.
-The horses went mad with terror
at the wild shouts, which echoed
and re-echoed ever more loudly
from the forests
and mountainsides,
while chance blows and wounds
so panicked them
that they wrought havoc
among the men.
[ Horse neighs ]
-You can imagine the noise,
the chaos,
the animals turning around,
people dodging,
trying to take cover.
People are falling
into the river.
And there was no way for them
to defend themselves.
-The tribesmen took
whatever plunder they could.
♪♪
By the following day,
they were gone.
♪♪
Hannibal sustained huge losses,
his men and animals
scattered across the gorge.
The horses proved to be
a liability in the mountains,
and their panic
only made the attack worse.
But they were a crucial
military weapon
that Hannibal
could not do without.
Half of them belonged
to his elite mounted force.
-The Numidians were
light cavalry.
They came from North Africa.
They were lightly clad
and famously rode
without saddles
and even without bridles.
They used
just a simple neck rope.
that's all they had.
♪♪
-The Numidians were armed
with fistfuls of javelins,
riding at the enemy
and repeatedly
throwing their spears.
They were hit-and-run troops.
-Riding without a saddle?
Stirrups hadn't been invented.
Riding without a bit
and a bridle is challenging.
It's only possible
on a fantastically trained horse
like this.
-The fact that the Numidians
actually went into battle
like that is mind-blowing.
I can't imagine.
But they must have had
such control,
such a relationship
with their horses.
This horse should follow me.
Hup!
So without any tack,
without bridles and stirrups
and all of that sort of thing,
he's silent, it's stealthy.
It's the perfect horse
for scouting.
Imagine them in the Alps.
If you're going over
treacherous terrain,
you can get off,
and the horse will follow you.
-On Hannibal's journey,
the Numidian cavalry
were frequently sent ahead
to gather intelligence.
And they possessed
a special skill
that gave them
the element of surprise.
-They would lay
their horses down.
[ Clicks tongue ]
It's perfectly comfortable
for the horse.
There he goes.
There!
Look at that.
Now, just think how useful
that is if you're a scout.
You can get really low
behind the tall grasses
and scout the enemy's camp,
count their numbers.
Then they could simply get
on their horses.
[ Grunts ]
They were the eyes and ears
of Hannibal's invasion force.
[ Clicks tongue ]
Hah!
-But the horses weren't
the only animals
that had to endure
the long march
to the top of the mountain.
So, too, did Hannibal's
famous elephants.
At the Royal Veterinary College
in London,
Professor John Hutchinson has a
rather grisly piece of evidence
that reveals why elephants
are so well-suited
for long and hazardous journeys.
-Back foot.
-It is the left hind foot
of an adult Asian elephant.
-Donated to science by a zoo,
it shows that elephants,
surprisingly,
can be very good
mountain climbers.
-So you can see that
he's up on tip-toe --
that's really remarkable
about elephants.
So you can see the heel up here.
That would be the ankle joint.
And then the middle toe,
the third toe, going down here.
So the elephant's up on tip-toe.
-I love that, the fact that you
look at them from the outside
and they look so sort of
straight and flat-footed.
-Mm.
-But then you look inside them,
and it's a completely
different story.
-Yeah, it sure is.
And then look at what
we have here
on the back half of the foot.
There's this massive,
yellowish, white tissue.
It's all fat pad.
Just like our heel pad
on our foot, but massive.
-When you imagine an elephant
moving through
the mountainous areas,
they might have been better off
than something with a hoof.
-Yeah.
Elephants have a foot that
is able to change its shape
to suit the environment.
-But it's not just
the structure of the foot
that makes elephants
well-adapted
for Hannibal's mission.
They are also very efficient
when in motion.
-As we see in this video,
the limbs are really straight
when they're supporting the body
and walking,
so they're like pillars.
The elephant
only flexes its joints
mainly when the feet
are off the ground,
so the muscles don't have
to exert as much force
to support an elephant's weight.
-Perfect for
long-distance travel.
-It is. They have a really
flexible way of moving.
And very steep slopes,
they'll get down
on their knees,
basically, and crawl along
to get up high slopes.
They have that kind of stability
and economy
that is uniquely elephant.
[ Bird cries ]
♪♪
-And there's proof that
elephants can cross the Alps...
-[ Laughs ] Crazy.
-...thanks to an
extraordinary experiment
conducted almost 60 years ago.
-Wow.
Actually, Jumbo looks larger
than I was remembering.
-In the summer of 1959,
British engineer John Hoyte
led a team of scientists
and explorers
on one of the most ambitious
experimental archaeology events
ever attempted --
taking an elephant over the Alps
in Hannibal's footsteps.
Sir Richard Jolly
was second in command.
-The scientific part
of our expedition
was a very careful checking
of Jumbo's speed
along the level
and when ascending
towards the summit
and as high
as 2,083 meters.
We were seeing whether
the difference in altitude
and the climbing challenge
slowed Jumbo down in any way.
And the short answer was
no, it didn't.
I think the elephants, they're
very sensitive creatures,
and if well-trained,
very confident
and in control of themselves.
[ Laughs ]
Yeah, and there's Jumbo
having some fun.
Good, old Jumbo.
Hmm.
-So elephants, despite living
in warmer climates,
can endure the cold and
alpine terrain in short bursts.
[ Elephant trumpets ]
With winter approaching
and the troops delayed,
Hannibal needed
to speed up the march,
so he loaded his
pack animals with rations.
Even the humble donkey
was essential.
Tori and Eve are attempting
the final leg
of Hannibal's climb into Italy,
going up to
the Col de la Traversette
and testing out how
the army would have coped.
-If you're on a mission
to be as quick,
moving as fast
and as light as possible,
then you're gonna always
have to trade-off
between what you carry
and what you collect.
And so the more you carry,
the less time you've got
to spend foraging.
-And once he starts to go
up to the mountains,
he's gonna have to be carrying
an awful lot of food
because there really isn't
much capacity up here to forage.
-The donkeys would have carried
about 220 pounds worth of hay,
enough food to feed
one horse for 20 days.
However,
Hannibal had 9,000 horses
and 37 voracious elephants.
Using historical records,
scholars have estimated
how much food the troops
and pack animals needed.
But for the elephants,
it's not clear.
-Mm-hmm.
Mm-hmm.
-And they also eat the grass
outside, of course.
-Si.
-Elephants are big,
hungry beasts.
An adult elephant can consume
up to 300 pounds of food
in a single day
and a lot more
if constantly on the march.
[ Bird cries ]
As they pushed on toward
the Col de la Traversette,
Hannibal's exhausted army
would have been spread
across 20 miles
of the mountain range.
The ancient texts state that
in these barren mountains,
the food supplies ran out.
♪♪
-The animals were nearly dead
from starvation,
since the high passes
were almost
totally devoid of vegetation,
and whatever fodder
there might have been
was buried under snow.
-Something
had clearly gone wrong
in Hannibal's planning.
-We're gonna stop there
just a second.
-The team encounters a problem
that Hannibal himself must
have faced in early November.
-Now we are up to 2,500
meters elevation,
and the path become
really, really hard, difficult
because it's steep
and really icy
and with the donkey,
we can't, go through.
For us, it can be okay,
but with donkeys,
it's impossible, for sure.
-And then you get
something like this,
and there's no way
you'd get a beast up there.
They'd have to go ahead
and hack the ice off.
And even then, you can
imagine the situation
where something lost
its footing and just slid.
-We have so many tales of it.
And it's amazing that two
or three times
we get this sense of these
pack animals knocking people
and themselves and other horses
and everything off the pass.
-Many pack animals must have
died on these steep, icy slopes.
Losing any of them
would have been a real concern
for an army wholly dependent
on the food they carried.
-As you lose your pack animals,
like, it's not just the beast
that's dead.
It's, you know, that's --
that's, 100 kilograms of load
that you can no longer
take with you.
That's 20 days of horse feed.
-And that's what
Polybius says
is, by the time they get
over the other side
to anywhere that's good grazing,
the animals are starving.
-Hmm.
-So, I mean, that's it.
They've lost so much
of their supplies
just coming up the sort of
dangerous routes like this.
♪♪
-The army marched for
nine days in the Alps,
camping in the freezing cold,
moving night and day.
♪♪
At long last,
after a desolate climb,
Hannibal reached
the Col de la Traversette.
From high atop the mountain,
the view of Italy
and the prospect of conquest
stretched out before him.
-Here we are,
France on one side,
Italy on the other,
standing on the border.
-His army must be spread out
all down the valley.
It takes two days
for everybody to come --
30,000 men
and maybe 10,000 pack animals,
and, of course, 37 elephants.
♪♪
-Hannibal needs
to make them believe
that they can do
what they set out to do.
And he encourages his army
with stories
of all the riches
and the wealth to be won
and of all the heroic adventures
that lie ahead of them.
-The monumental Alps, with their
snowy spires and craggy slopes,
met their match.
Now, for the first time,
scientific evidence
is confirming
the historic event --
that Hannibal crossed
these mountains at the highest
and most difficult pass
of them all,
the Col de la Traversette.
-Finally,
we are pulling together
some scientific evidence
that this is the route
that he took across the Alps.
And who would have expected
that this could be
coming down to something
as simple and tiny
as the bacteria
hidden in the soil?
-We finally had narrowed
the pass down to one place.
-A journey that became legendary
has now been made real.
-Whilst it was difficult,
whilst it would
have been bloody,
there would have been deaths
of both people and of animals,
at each stage,
I don't think any of those
problems were insurmountable.
If you're willing to push,
then why not?
You could do it.
-Hannibal's invasion of Rome
over the Alps
sent shock waves
through the ancient world.
By the end of the year,
he had won two decisive
battles on Roman soil.
Carthage was safe for now.
For 15 long years,
he waged a campaign of
annihilation throughout Italy.
But eventually,
Rome stood strong once more,
and the tide of victory turned.
Hannibal was finally
defeated on home soil,
and Carthage was left in ruins.
But 2,000 years later,
his incredible journey
over the Alps
stands as a testament
to his unflinching determination
and military genius.
-This was undoubtedly
the most difficult pass
Hannibal could have taken.
And we sort of have
to ask ourselves,
why did he take
the hardest route?
And what probably drove
that decision
lay in what made
the man who he was.
Because the more
difficult the journey,
the more difficult
his quest almost,
the greater his
heroic status would be.
2,200 years later,
we're still absolutely
fascinated by Hannibal
and especially by this journey
he made over the Alps.
-He created the myth,
and we still believe it.
-Hannibal's journey
was legendary,
and now we know
it wasn't a myth.
♪♪