Unearthed (2016–…): Season 7, Episode 12 - Seven Wonders of Ancient Rome - full transcript

A lost villa
buried near the colosseum,

epic engineering secrets
of the pantheon's design,

astonishing mysteries
of ancient aqueducts.

These,
and other new discoveries,

are shining a light on
seven wonders of ancient rome.

These iconic megastructures

set the benchmark
for roman ingenuity.

How were they built?

And what secrets
do they still conceal?

Today investigators use
pioneering archaeology...

This is something
much more precious.



There's writing on them.

...And forensic technology...

Reading the papyrus
has been the biggest challenge

that I've had
in my professional life.

...To decode the mysteries

of ancient rome's
world famous icons.

Across the empire,

these massive monuments
define a global superpower.

How do ancient engineers

overcome
the incredible challenges

of building
bigger than ever before

across multiple continents?

We reveal how the most
powerful empire on earth

enters a new age
of engineering achievement



to build the seven wonders
of ancient rome.

UNEARTHED - SEASON 7
EP-12 - Seven Wonders of Rome

Subtitles Diego Moraes

the seven wonders
of the ancient world

span three continents

and thousands of years
of history.

But 2,000 years ago,

a new generation
of engineering wonders

rises to take their place.

How do the romans match
the engineering might

of earlier ancient
civilizations...

...And ensure their monuments
still stand today?

A clue lies
in the first wonder...

The colosseum.

A giant complex at the heart
of the ancient city of rome.

Its sheer size rivals

the largest of
the original ancient wonders...

The great pyramid of giza.

The colosseum is an arena
of death and magic,

of potent spectacles with
the power to sustain an empire.

Buried within its walls
are clues that reveal

this is much more
than just a theater.

The colosseum still
strikes our heart today.

You can still feel
the same feeling

that the roman spectators
felt at the time

of the performances.

Today, teams of experts
are exploring deeper

than ever into the heart
of the building,

to solve the mysteries
behind its construction

and how it holds infamous
gladiatorial battles.

And each year,

archaeologists uncover
new evidence of life

in and around
the monumental arena.

Now excavations
for rome's new metro line

that runs right past
the colosseum

reveal something extraordinary.

Workers discover
the remarkable remains

of a luxury villa.

They investigate the findings

to reveal it belongs
to a military commander.

It features 14 rooms,
complete with stunning frescos

and mosaic floors.

As work continues on the metro,

archaeologists hunt
for new evidence

of this ancient civilization

to reveal how the hidden secrets
of this vast ruin

ensure the colosseum
still stands today

when so many of the original
wonders of the ancient world

have fallen.

Concealed under
the colosseum's skin

is a complex system of pillars,
arches, and vaults.

They spread the colossal load
of nearly a quarter

of a million tons of stone,

allowing this building
to tower 157 feet

above the streets of rome.

In the stadium, space for up
to 80,000 spectators,

big enough to hold
the super bowl.

Built into the arena floor,

a subterranean maze
of tunnels and chambers,

the secret domain of the
empire's deadliest servant...

The gladiator.

The colosseum and the men
who fight in it

are the most iconic symbols
of the roman empire.

Even today, the colosseum
is an impressive structure.

The original ancient wonders,

like the lighthouse
of alexandria

and the temple of artemis,

have long since disappeared.

But incredibly,

this roman wonder's
157-foot-high walls

still stand after nearly
2,000 years.

This building
is iconic as it represents

the evolution
of the roman empire

from its rise through its fall.

Yet despite
its crumbling exterior,

the colossal colosseum
still mystifies archaeologists.

1,900 years ago, it looks
even more magnificent.

The stone, now weathered
after two millennia,

would have shone
brightly polished.

In the perfect archways,
statues of marble and gold

trumpet the glory of rome.

Its walls stretch nearly
2,000 feet around the outside,

rising higher than any
other structure in the city.

This is the biggest
single building

ever created by the romans.

But how do
ancient roman engineers

make this monumental structure
so robust

it still stands today?

A clue lies hidden
in the bay of naples

to the south.

Here, underwater archaeologists
discover the remains

of an ancient roman town
called baiae.

Brushing away the silt
reveals a stunning mosaic

buried inside the remains
of an opulent villa.

Archaeologists send
loose fragments of the mortar

that holds it together

to mineralogist
mauro francesco la russa.

Mauro believes these ruins
survive thousands of years

because the builders
use super strength materials...

Concretes and mortars unique
to the bay of naples.

Mauro discovers the secret
of the materials' strength

using a high-power
electron microscope.

The volcanic rock creates an
incredibly durable material

when mixed with lime.

The discovery
of the super strong concrete

not only builds this ancient
underwater town,

it also transforms
the roman empire.

This wonder material is the key

to ensuring rome's expansion
and position

as a new global superpower.

It allows engineers to construct
the empire's finest monuments,

including rome's first wonder...

The colosseum.

But the colosseum
isn't just famous

for its monumental structure.

The giant amphitheater carries
a message from rome's leaders...

Follow us
and we will keep you thrilled.

The empire's ancient wonders
glorify the strength

of roman imperial power.

And the stars of the show
are the gladiators.

Very little is known about
these legendary warriors.

But hidden in the vaults
and columns of the colosseum

are tantalizing clues
to their origins.

These warriors are the biggest
attraction in the empire.

Inside the arena, they became
the stars of a true spectacle.

Deep within the maze of brick
walls under the colosseum

lies a secret entrance

to their violent
and bloodthirsty world,

a doorway connecting
a 180-foot-long tunnel

that brings the fighters
into the arena.

2,000 years ago,
this leads to rome's

fabled fighting school,
the ludus magnus.

Standing right next
to the colosseum,

this is the breeding ground

of the most powerful
roman propaganda tool...

The gladiator.

These fearsome warriors

champion the ferocity
of roman combat skills,

a show of deadly force
for all to witness.

But there's a mystery.

No gladiator bones

have ever been discovered
at the colosseum

to tell us more about
the lives of the gladiators.

Are they just the empire's
disposable thugs?

Fabian kanz investigates
these fearsome warriors.

He has unearthed
something astonishing...

The only gladiator bones
that have ever been found.

They are discovered in
the grounds of an amphitheater

that once sits on the edge
of the empire

in what's now modern-day turkey.

Fabian thinks the men,
far from being disposable thugs,

are treated more like
valued athletes.

And fabian discovers
that these incredibly rare bones

can tell him even more
about the lives and diet

of these men.

Chemical traces of
the food they eat

builds up in their bones.

To analyze the chemicals
in these gladiator skeletons,

he grinds a bone sample into a
powder and adds it to a liquid.

When he sprays the liquid
into a flame,

it will burn
with a signature color,

a fingerprint that reveals
the chemicals

locked inside the bone.

Strontium is a mineral
similar to calcium

and strengthens bone.

Fabian thinks the strontium-rich
gladiator bones

are a clue they are fed
a special diet.

These new heroes of the
colosseum put on a spectacle

that shows off
the might of the empire

and rouses patriotic passion
in its citizens.

The astonishing arena
becomes a showcase

of overwhelming imperial power,

bolstered by
the incredible strength

of the roman concrete and mortar
that builds it.

These features ensure
the colosseum still stands

as an epic engineering
masterpiece.

Today it is regarded as
a true wonder of ancient rome.

But beyond theatrical spectacle,

the romans need practical
engineering solutions

to help their cities function.

How does the empire supply
its people

with the basic amenities
to survive and thrive?

Does the next roman wonder,
the aqueduct,

hide a secret to the one

of the colosseum's
biggest mysteries?

And can gruesome discoveries

in the ancient city
of herculaneum

reveal what devastates
the population?

For five centuries,

the roman empire
is the mightiest on earth.

And one extraordinary wonder
stands at its heart,

the colosseum.

The colossal arena matches
and even surpasses

the greek's list of original
ancient wonders.

The colosseum stands
as an icon of imperial power,

and its mighty construction
is possible

thanks to the romans use

of super strong concrete
and mortar.

But the secret of roman success

is not just in the materials
its engineers use.

The romans maintain power
throughout their empire

with constant innovation.

They keep their burgeoning
cities under control

by providing basic amenities
like fresh water.

Secrets to how they do this

lie hidden inside ancient rome's
second wonder...

The pont-du-gard aqueduct.

A vast megastructure
in the roman province of gaul,

now southern France.

It is a monumental icon
of roman technology.

Spanning the river gardon,
it carries water over 30 miles.

Built in the 1st century a.D.,

it is considered the tallest
roman construction in the world.

This ancient wonder still stands

with help from the super strong
roman mortar.

Aqueducts represent the pinnacle

of their hydraulic
engineering prowess.

Engineers construct aqueducts
across the empire,

but they are critical
to the functioning of rome.

These giant structures

cross hills, valleys,
and packed cities.

How do engineers conquer
these formidable obstacles

to build these
massive structures?

To keep water flowing
from springs surrounding rome,

engineers dig trenches
around hills,

and cover them
with bricks and earth.

To overcome high mountains,

they dig tunnels
right through them

with shafts in the roof
for ventilation.

To cross ravines and valleys,

they funnel the water
through lead pipes,

pushing it up the hill
on the other side.

And to channel
the water into rome,

they build mighty
arched aqueducts,

some over three stories tall.

Today, in the heart of rome,
the magnificent trevi fountain

is still supplied with water
from an ancient aqueduct.

But in the first century,

there could be another
astonishing use

of aqueduct water.

The colosseum,
ancient rome's first wonder,

plays host to an array
of deadly championships.

But one colosseum legend
is cloaked in mystery.

Are giant sea battles
staged inside this arena?

The colosseum
was a real showpiece,

so I think it's not
improbable at all

that the romans would hold
such a sea spectacle.

How can this stadium possibly
be filled with battleships?

There's a clue buried
right next to the colosseum...

A three-foot-wide tunnel that
runs right beneath the walls.

Archaeologists believe that it
may feed into a labyrinth

of strange, shallow channels...

Channels that lead
to the center of the arena.

Could these be the remains
of a gigantic hydraulic system

with the power to flood
the colosseum with water...

...So the emperor can watch
full-blown sea battles,

the ultimate display of roman
might and ingenuity?

The legend of the colosseum's
sea battles

comes from a single
ancient text.

It describes the arena
flooding in a matter of hours.

How could this be possible?

High up in the mountains
outside rome,

valerie higgins investigates
this mystery.

She starts at one of rome's
famous aqueducts,

the aqua claudia.

It once channels waters
46 miles into the ancient city.

We want to understand how much
water could go through it.

We want to understand how
it delivered water into rome.

How difficult is it for
the romans to fill an arena?

Valerie works
with adriana morabido,

an expert in roman
subterranean tunnels.

Along here, we can see the level
of the water going along.

Maximum half a meter of water,

and then the rest
was just empty.

Obviously, it was going down
by gravity, not by pressure.

Valerie wants to work out
whether this aqueduct

could supply the 3 1/2 million
gallons of water

needed to fill the colosseum,

as the legend describes.

What we would like to do

is measure the height
of the aqueduct,

and then measure it
in another place, as well,

so we can work out the gradient.

The slope of the tunnel floor
will help them calculate

how fast water flows into rome.

So here is 110, and there is 87.

So we have a 23 centimeters'
difference in 9 meters.

But what they find
is a very gentle slope,

a drop of just 9 inches
in 30 feet.

The water here
would flow far too slowly

to fill the colosseum
to nearly five feet

in just a few hours.

It's an extraordinarily
large arena.

It isn't filled very high.

It's only filled to like
a meter and a half.

But nevertheless, it's really
hard to imagine water

coming through here
filling the colosseum.

But valerie believes
the aqueduct

may not tell the whole story.

She thinks there may be
a crucial piece missing

from this complex puzzle
of roman plumbing.

Multiple aqueducts, 11 in total,

channel freshwater
directly into ancient rome.

Valerie's theory is that
when the colosseum is built,

a huge water tank is added
somewhere near the amphitheater.

The tank stores enough water to
flood the colosseum in one shot.

Beneath the amphitheater,
the network of circular channels

distributes
the stored water quickly

and evenly into the arena floor,

ready for a spectacular
sea battle.

Then, four huge
drainage channels

opened to flush
the water away again

in time for the next games.

But if a storage tank that holds
3 1/2 million gallons of water

is the key to filling
the colosseum,

where is it?

Valerie goes on the hunt

with the help
of dr. Mateo baroni,

they track the route of
the aqueduct through urban rome.

Near the colosseum,

they discover
the partial remains

of a much larger structure.

Could it be the missing
piece of the jigsaw?

We have some remains
of a monumental fountain.

What is interesting about
the monumental fountain

is there was a water
storage unit in it.

The water storage tank
that once feeds the fountain

is gone.

But valerie thinks
it would have been big enough

to hold the volume of water
required to fill the colosseum.

It's six meters difference
between here and the colosseum.

It's very steep going down here.

It descends quite fast.

You could get a big,
hydraulic pressure from here

that would push the water
into the colosseum very quickly.

So I think it's a feasible
proposition.

Thanks to the ingenuity
of roman water engineers,

the colosseum stages spectacles

that become legendary
across the expanding empire.

The romans'
technical innovations,

like hydraulic engineering
and power over its people,

are secrets to their success.

They allow the empire
to expand across continents

and build enduring monuments

that outlive the original
seven ancient wonders.

But how far from rome
does the empire stretch

and how does the roman army
meet its match?

A clue lies in northern britain

with the romans' next
ancient wonder...

Hadrian's wall.

And in the heart of rome,

despite the empires
advanced construction skills,

one of the most
incredible wonders

has all but vanished.

How?

Rome's seven wonders are
incredible sights to behold.

Stunning monuments that hide
ingenious technical innovations.

They are the equal
of the seven original wonders

of the ancient world.

Romans built their wonders
to last.

And rome's third wonder
is no different.

Hadrian's wall,

an astonishing
ancient megastructure.

A mighty 73-mile-long
man-made barrier of stone.

Like all of rome's wonders,
it's built to last.

By the first century a.D.,

the roman empire expands
across the mediterranean,

north africa,
and crosses europe into britain.

The roman army appears
an unstoppable force.

So why build a wall here?

And how does the construction
of this gigantic wonder

ensure the empire's dominance
in britain?

Hadrian's wall is the largest
of rome's great wonders.

It splits the island
of britain in half

from east to west,
coast to coast.

The man behind the wall
is the great emperor hadrian.

But its story is shrouded
in mystery.

Hadrian's wall
isn't written about

by very many roman authors,

so we don't ultimately know

what the romans thought
hadrian's wall was for.

Archaeologists once think

the wall is a symbolic statement
of rome's power.

Now, new excavations
by teams 500 strong

are discovering
the wall's original layout.

And it reveals
a more forbidding purpose.

In 125 a.D.,

roman engineers
build hadrian's wall

with four million tons
of solid limestone blocks

creating the biggest structure
rome ever builds.

Its wall is up to 10 feet thick,
standing as tall as three men.

From mighty stone towers
every third of a mile,

soldiers keep watch 24/7.

And gigantic forts hold almost
10,000 troops to keep guard.

What can the construction
of this ancient wonder

tell us about who the romans
face in this distant land?

Hadrian's wall gives teams
of archeologists

a huge opportunity
to uncover new insights

into how the mighty empire
builds big.

Archeologist rob collins
has studied hadrian's wall

for 20 years.

He believes this ancient wonder

is rome's greatest
engineering achievement.

It's very easy to be wowed
by the colosseum in rome.

But actually if you
think of logistics,

that's a piece of cake.

Hadrian's wall is a much bigger
logistical construction project.

Today rob explores
a section of the wall

at remote spot called steel rig.

What we see with hadrian's wall

is when the romans
have that choice,

and you have
a dramatic windswept crag,

the romans will build
the monument

on the front edge of that crag,

so it really exaggerates
the height of the wall.

As well as building
on top of huge cliffs

to make their walls seem bigger,

the romans dig vast ditches
beneath it.

When you add those together,

hadrian's wall is much more of
a defensive monumental barrier.

The mighty roman army
invades britain in 43 a.D.

After 80 years of fighting,
they control most of the island.

Britain is supposedly at peace
in 117 a.D.

When emperor hadrian
comes to power.

But this vast monolithic wonder
tells a different story.

This north facing crag
is actually telling us

who the monument
is being built against.

They're building it on behalf
of the people to the south,

who are the residents
of the province of britannia.

And we can see that
they're trying to keep out

those peoples to the north,

who we traditionally
call barbarians.

These barbarians are

the native people
of northern britain...

Ancient iron age tribes
of fearsome warriors.

But surely they are no match
for the mighty roman army.

The answer could lie one mile
south of the wall,

at vindolanda.

Here hundreds of archaeologists
work on an ambitious project.

They dig up an entire roman fort

built just a few years
before hadrian's wall.

The excavations here reveal
evidence of fierce fighting.

Andrew birley is the site's
lead archaeologist.

Vindolanda offers us
an opportunity

to see exactly what's going on
in this landscape

just before hadrian's wall
is being built.

During a recent
analysis of previous finds,

the team uncovers
something unusual...

A small piece of leather
cut into the shape of a mouse,

perhaps a child's toy dropped

while fleeing
from a fierce battle

or a soldier's idea
of a practical joke.

The mud layer at vindolanda

is a time capsule
of roman relics

with coins from hadrian's time

and even a 2,000 year old
wooden toilet seat.

There is evidence of heavy
fighting... arrowheads, swords,

and the tombstone
of a roman centurion.

But the most remarkable haul

is hundreds
of mysterious chunks of wood.

Sketched onto them
is ink handwriting.

It's the largest find of roman
manuscripts in western europe.

They record life on the frontier
before hadrian's wall is built.

Can these tablets explain
why the romans are so afraid

of the barbarians
to their north.

Andrew handles the latest
discovery with great care.

Each postcard sized tablet
is barely 1/16 of an inch thick.

One gives a unique insight
into roman relations

with the barbarians
of the north.

This is an intelligence report

talking about british cavalry,

and basically saying
how irritating they are there.

They have many horses,

but they have to basically
get off their horses

to throw their spears... they're
not very, very effective.

It's written around a 100 a.D.,

20 years
before the wall is built.

The tablet reveals the fierce
northern barbarians

wage a guerrilla war
against rome.

They have to respond.

They've lost a lot of soldiers,

and one of the responses is
to build hadrian's wall.

To shut down and lock down
the frontier of roman britain.

In the second century a.D.,

the roman army isn't just
locking down

the border in britain...

The expanding empire creates

over 4,000 miles of
new frontier,

which their legions
are struggling to defend.

To stop aggressive tribes
in africa and asia,

the romans build huge forts
to house their armies.

To suppress barbarians
in europe,

they build long palisades of
wooden stakes and watchtowers.

And after a deadly war
in britain,

emperor hadrian orders
a massive stone wall

running across the whole island.

Hadrian's wall is
an epic engineering masterpiece.

Built to defend against
northern barbarians.

But how does the roman army
use this ancient wonder

to defeat their enemies
to the north?

And does the empire equip
the soldiers here

with its infamous
deadly combat skills?

Discoveries near the wall
hold a clue.

And later, in the heart
of ancient rome,

how do engineers defy gravity
to build the pantheon?

Hadrian's wall

is ancient rome's
biggest megastructure.

The vast imposing edifice

reflects the empire's
engineering skills

and massive military might,

a structure worthy
of ancient wonder status.

It's built to defend
against attacks

from northern barbarians.

Hadrian's wall marks
the northern limit

of the empire's reach.

Having conquered
across three continents,

the empire now needs
this massive barrier

to defend its new land.

How does the roman army
use the colossal construction

to take the fight to the enemy
on their own turf

and maintain an empire
of unprecedented longevity?

Evidence north of hadrian's wall
offers a clue.

20 miles beyond the wall,

archaeologists find evidence
of a ferocious battle at a site

known today as burnswark hill.

In roman times,

burnswark is one of the largest
hill forts north of the wall.

An ancient center
of tribal power,

its walls provide shelter
for 2,000 barbarians.

Around the hill fort,

archaeologists unearth evidence
of roman warfare...

Dozens of carved red sandstone
balls the size of grapefruits,

deadly missiles fired
from roman catapults;

and hundreds of lead pellets
the size of marbles.

What can these relics
of ancient battles

reveal about how the romans use

this wonder
of military technology

to defeat enemies
north of the wall?

Archaeologist john reid uses
pioneering drone technology

to hunt for clues to this
2,000 year old mystery.

Okay. Ready to roll.

The high flying camera

reveals a huge network
of ditches

at the base of burnswark hill.

They mark the edges
of two roman camps

that surround
the enemy's hilltop fort.

John thinks their close position
is a clue

to the invading romans'
plan of attack

and reveals what makes
rome's wonders possible...

The unstoppable might
of the roman military machine.

The romans know that the natives

did not have distance weapons.

For them, it's all hand-to-hand,
face-to-face fighting.

Many roman soldiers

in this strategic advance
from the wall

are highly trained
in the use of the slingshot.

John believes the position
of their camps

is so roman slingers
can bombard enemy troops.

He uses metal detectors
to search this hill fort site

for evidence
of an ancient aerial attack.

We have a lead slinged bullet.

What this is effectively
is an iron age slug.

It's a bullet.

This would have been shot
from a sling

and aimed at some
poor individual.

John finds over
700 slingshot bullets

at the site.

To get a better idea
of how they're used in battle,

he works with andy nicholson,
an expert in ancient warfare.

Andy and john investigate

the lethal range
of a roman sling.

To do this,
they use a replica weapon

and a ballistic gel,

which has the same resistance
as human flesh.

The slingshot
is a handheld rope pouch

that launches lead pellets
at a deadly velocity.

You're looking at a sling bullet

that's travelling at over
60 yards per second.

The impact damage is phenomenal.

And it not only breaks ribs,

it can cause internal rupturing
and bleeding.

If one of these hits you
in the head,

then that's the end of it.

Andy's tests show
the roman sling

is the handgun
of the ancient world...

A killer weapon
at over 100 yards.

The roman army
is using maximum force

to advance its new invasion
of the north.

John and andy plot the locations
of their ancient finds

on a map of the site.

Their analysis allows them
to piece together

how this pivotal battle unfolds

and how the romans destroy
all their enemies

to expand the empire
and construct more wonders.

The romans build two camps
on either side of burnswark.

From here, they deploy their
catapult and slingshooters.

They rain heavy fire
down into the fort

to terrify and soften up
the enemy.

Then 5,000 heavily armed ground
troops rush from the camps

and storm the fort.

Any survivors trying to escape

die in a hail
of roman slingshot fire.

Once the assault
actually started,

it was complete extermination
of every living being

on the summit of the hill...

Men, women, and children.

This annihilation

is designed
to show all other tribes

what's in store for you if
you dare stand up to the romans.

The roman troops
blaze a destructive path

75 miles north
of hadrian's wall.

The wall's huge
military infrastructure is key

to supplying this new invasion
with weapons, supplies,

and troops.

Today, this ancient wonders
defensive strength

is no longer needed.

And 1,600 years
after the empire's decline,

hadrian's wall
still stands strong,

stretching from coast to coast.

It's a permanent reminder
of the almighty strength

of rome's military machine.

But in the heart of modern rome,

one ancient wonder
is surprisingly still in use.

How has the near
2,000-year-old pantheon

survived this long?

And what secrets does the buried
roman city of pompeii conceal?

The colosseum, hadrian's wall,

and the pont-du-gard aqueduct...

Breathtaking wonders
the romans build to last.

They surpass the icons
of earlier civilizations.

The fourth great wonder
of ancient rome

is a remarkable temple
dedicated to all the gods.

The pantheon.

It stands strong after
nearly two millennia

in the heart
of the eternal city.

Impressively,
it's still in use today.

Millions of people
visit it each year.

Its longevity is testament

to ancient rome's colossal
construction expertise.

The pantheon is built
by rome's most prolific builder,

emperor hadrian,
around 126 a.D.,

just after he orders
construction of his mighty wall.

The pantheon takes its name
from the greek "pantheos,"

meaning "all gods."

hadrian builds
this remarkable wonder

to honor rome's
greatest deities,

including king of the gods,
the mighty jupiter,

his brother neptune,
god of the sea,

with his iconic trident,

and mars, the famous god of war,

believed to be the protector
of the roman state,

hadrian desires nothing
but the best for his new temple.

But building a monument
worthy of the gods

pushes roman engineering
to its limit.

Hadrian designs
an elaborate temple

with a 142-foot rotunda,
a greek style colonnade,

and a mighty domed roof.

For the colonnade,

he ships in 16 granite columns
from egypt,

each 39 feet long,
weighing 60 tons.

For the rotunda, his engineers
build a series of arches

and stack them
on top of each other.

But building
the 142-foot domed roof

will take some innovative
engineering and design.

The development
of super strong concrete

proves the romans
have a powerful command

of building techniques.

It allows this ancient wonder
to stand the test of time

when so many have fallen.

But concrete
is incredibly heavy,

and nothing less
than a giant, unsupported dome

will do for hadrian's roof.

This poses a massive
structural challenge.

So how do ancient engineers
build this gravity-defying dome?

If they build the roof
from solid concrete,

it could weigh 20,000 tons

and collapse
under its own weight.

To make the concrete mix

they use in the top of the dome
lighter,

they replace the heavy
basalt-stone ingredient

with a much lighter
pumice stone.

They make the dome thinner
towards the apex

and cut decorative recesses
into it

to shed even more weight.

And to stop the roof from
spreading out and collapsing,

they install strong
concrete rings around its base,

like steel hoops
around a barrel.

And there's one final
architectural solution.

At the center of the dome,

engineers cut
a 27-foot-wide hole...

An oculus.

It reduces weight
at the dome's weakest point,

but it also illuminates
the temple

with a revolving
circle of light.

The pantheon's
breathtaking design

inspires architects
for millennia...

The duomo in florence, Italy,
a medieval masterpiece,

the united states capitol dome
in washington

made from cast iron,

and a 21st century version,

the singapore national stadium

that boasts a world-beating

1,017-foot
retractable dome roof.

However, today,
the pantheon still remains

the largest unsupported
concrete dome in the world.

This epic concrete wonder

is a temple still worthy
of the gods.

It represents the pinnacle
of roman technical innovation

and construction achievement.

The romans build to last.

It's what defines
their ancient wonders.

But one of rome's
imperial masterpieces

has mysteriously
disappeared from view...

Emperor nero's
magnificent golden palace.

Can traces of it be found
buried beneath rome?

And what secrets does the frozen
city of herculaneum hide?

The pantheon is a masterpiece
of roman engineering.

Its ingenious design ensures
it still stands today.

But another
extraordinary structure

rises decades before
the pantheon's construction...

Ancient rome's
fifth great wonder,

the domus aurea,

emperor nero's golden palace.

Its legendary size makes it

one of the largest
palace complexes in history.

Six of the seven original
wonders of the ancient world

are built in deference
to resurrection and the gods.

The hanging gardens of babylon

is the only ancient wonder
built simply for pleasure.

And nero's golden palace
is the same,

an opulent residence
for the emperor alone to enjoy.

Today, only fragments
of this vast residence remain,

but it's built after
a devastating tragedy.

In the early hours
of July 19, 64 a.D.,

a spark triggers
a deadly chain reaction.

A devastating inferno breaks out

at rome's famous
chariot racing track,

the circus maximus.

The fire spreads
across the city,

destroying most of the capital.

After the flames die down,

emperor nero orders
a vast new palace complex

to be built in the ashes.

It's called the domus aurea,
or golden palace.

Archeologist valerie higgins

believes nero's reign
begins well,

but it descends
into cruelty and tyranny.

People had a lot of hope
in nero,

but they started to change
their opinion of him.

He murdered his mother.

And then he also started

these very self-indulgent

building projects.

Ancient writers
accuse the emperor

of burning down rome
to build a gleaming new city.

He even has a name for it...
Neropolis.

And at the heart
of this gleaming city,

nero builds his golden palace.

Hidden beneath modern rome

lie the traces
of this ancient mega palace.

Roman writers
describe a building

with hundreds of rooms,

surrounded by lush gardens

and covered with gold, jewels,
and mother-of-pearl.

Alongside,
a private boating lake,

bigger than
10 olympic swimming pools.

And at the entrance,
the crowning glory...

A giant bronze statue
of the emperor nero himself

that towers 120 feet tall.

The domus aurea
is a 200-acre residence

of unimaginable luxury.

Today, this wonder
has all but disappeared.

500 feet from the colosseum

lies the only surviving
section of palace.

Archaeologist
alessandro d'alessio

investigates the remains
of this wonder.

Alessandro searches for
what marks the domus aurea

as a true wonder.

Legend says the palace
hides an astonishing secret

that sets it apart
from other royal residences.

A banqueting room

that supposedly
rotates day and night.

For years, archaeologists think
that this octagonal chamber

is the rotating room of legend.

Hidden windows
give the impression

of the sun moving around it.

With this, historians believe

an actual revolving room
is just a myth.

But a new discovery in
this section of nero's palace

on the palatine hill

reveals that truth is often
stranger than fiction.

Buried beneath this canopy

are the ruins
of an incredible mechanism.

Two crumbling arches
are all that remain

of a giant branching structure
over 65 feet tall.

On the top,
archaeologists discover

strange holes
arranged in a ring.

Inside them is a soft clay,

possibly a lubricant,

a clue that they could've once
held bronze ball bearings...

20 of them spinning in unison,

revolving the floor
of the legendary dining hall.

This incredible building
sets the domus aurea apart

as a true wonder.

What does it take to build
such a magnificent structure?

Today, the remains are buried
deep behind these walls.

Archaeologist
francoise villedieu

hunts for evidence
of the ancient mechanism.

She heads down to
the base of the walls

to investigate.

This room is one of the most
sophisticated machines

in the ancient world,

but how do his engineers
power it?

Utilizing one of rome's
earlier wonders.

Does the emperor connect
a nearby aqueduct

to his palace complex?

The remains of the aqueduct

lie close to nero's palace.

Nero can divert its water

to the base of his
rotating dining room.

The water feeds
a huge waterwheel

two stories high.

It turns night and day
with the constant flow.

Connected to the wheel
are a series of cogs and gears.

These transmit the force
of the water up,

towards the rotating floor.

The dining room
perpetually rotates,

allowing banqueters
panoramic views of the city

both day and night.

This revolving masterpiece

is every bit as lavish

as the contemporary
writers describe.

It exemplifies
the sheer ingenuity

of roman mechanical engineering

and ensures nero's golden palace

becomes a true
ancient wonder of rome.

The empire's wonders
are built to last.

And have all withstood
the test of time.

It's what sets them apart

from the lost wonders
of the ancient world.

So what happens
to the domus aurea?

And what turns pompeii,

a seemingly normal roman city,

into a frozen ancient wonder?

The seven wonders
of ancient rome

represent a new level

of astonishing
engineering achievement.

They surpassed the original
wonders of the ancient world.

They last longer, soar taller,

stretch further.

They completely transform
how structures are built

and leave a lasting
engineering legacy.

To this day.

But the fifth roman wonder,
the domus aurea,

has all but disappeared.

Why?

Could the answer be found

in the origins
of the golden palace itself?

Nero builds his
magnificent domus

in the ashes
of the great fire of rome.

Ancient writers
accused the emperor

of deliberately
starting the fire

to clear space for it.

But are the stories true?

And if so, can it explain
the fate of the golden palace?

Archeologist antonio ferrandes

investigates the footprint
of nero's ancient wonder.

He wants to work out
if there is any truth

to the ancient accusations.

Antonio heads up
rome's ancient palatine hill.

He uses modern satellite imagery

to reconstruct rome
just before the fire.

Ancient writers claim

that nero wants all
of this prime real estate.

Intriguingly,
the footprint of the palace

matches vast swaths
of the destroyed areas.

The fire starts
at the circus maximus.

It rages over six days
in 64 a.D.

And destroys
nearly 2/3 of the city.

It leaves a blank canvas

for nero's audacious rebuild.

On the charred hill where
the roman elite once lived,

nero builds his golden wonder
with over 300 rooms

and his revolving dining room.

And in the valley where once lay
houses for the lower classes,

he erects a network
of opulent palaces

and fills the gardens
with wild animals.

Nero turns
a bustling city center

into one of the largest
private palaces in the world

right in the heart of rome.

The evidence is circumstantial

but highly suspicious.

So, could the ancient authors
be right?

Is the emperor capable
of burning down rome

in order to build his own
roman wonder?

Inside the last
surviving remnants

of this remarkable
golden palace,

archeologist
alessandro d'alessio

pieces together more clues.

Alessandro believes
the extravagant opulence

and sheer scale of the palace
is the reason for its downfall.

But instead,
the people send him a message.

Nero is overthrown.

The romans turn on
this ancient wonder,

believing its creation
is to blame for the fire

that devastates their city.

And after four years
of construction,

romans ransacked
nero's residence,

stripping off the precious
jewels and gold leaf.

They drained the lake
and buried the palace.

On top, they build rome's
greatest wonder,

the colosseum,

a symbol of a city
to be shared by all romans.

The ousted emperor
flees the city

and eventually commits suicide.

The controversial golden palace

is the only wonder
of ancient rome

that has not fully survived.

It celebrates
and commemorates just one man,

the emperor nero,

not the glory that is rome.

But it takes its place

on the list
of rome's great wonders

due to the scale of its ambition

and the innovation
of its technology.

Not all roman wonders are
vast palaces or grand monuments.

Herculaneum and pompeii...

Two ancient cities

that lie in the shadow
of mount vesuvius,

transformed
into spectacular wonders

when the mountain reveals
its startling power.

For centuries,
the romans build a vast panoply

of awe-inspiring wonders.

Amazing amphitheaters
and mega monuments

define an empire
of engineering achievement

that outlasts the original

seven wonders
of the ancient world

that come before.

The sixth roman wonder

is a wonder
for a very different reason.

Herculaneum...

An entire roman city
destroyed and preserved,

now locked in stasis.

Buried under 75 feet of debris,

a town frozen in time
for nearly 2,000 years.

Roads crisscross the ghost town

flanked on each side
by the scorched remains

of shops, bars, and homes.

But in its prime,

its streets are colorful
and vibrant.

This town is home
to over 4,000 people.

But just four miles to the east,

the sleeping volcano, vesuvius.

But exactly how does vesuvius
preserve the town?

And what makes it
a roman wonder?

Herculaneum is located
south of rome

on the bay of naples.

Now, archeologists come here
to uncover its secrets,

peeling back layers of debris
to reveal its fate.

In the remains
of ancient boathouses,

they make a shocking discovery.

They unearth hundreds
of skeletons huddled together.

But there's one intriguing
discovery that baffles experts.

In a building on the corner
of the main street,

a hidden room.

Inside, a stone plinth supports
the remains of a wooden bed.

And in the center,

the skeleton of a man,
buried where he sleeps.

Inside his exploded skull,
a strange discovery...

Unknown fragments
that looked like glass.

What is this bizarre material?

And what can it tell us
about the deadly event

that preserves this city,

transforming it
into an ancient wonder?

The man is locked
for 2,000 years

under layers of debris.

Forensic archaeologist
pier paolo petrone

is the first person
to investigate his death.

He believes this body
can reveal new clues

to what happens on the night
he dies.

Ciao. Ciao.

Pier paolo takes
the mysterious material

back to his lab

at the university of naples
to investigate.

There's only one phenomenon

capable of delivering
such devastation.

The infamous volcanic
eruption of mount vesuvius

in 79 a.D.

It destroys herculaneum.

The force of the eruption

is powerful enough
to incinerate flesh

and vitrify brains
in an instant.

But with such
a devastating force,

how has much of herculaneum
been preserved?

Geologist guido giordano
hunts for forensic evidence

to understand
what preserves the city.

He investigates
the volcanic rock

that covers the region.

This cliff is about 80 feet.

Now, this is enough
to completely bury the old town.

Guido believes
the different layers of deposits

are like a volcanic fingerprint.

They reveal exactly what happens
on the day of the eruption.

You can clearly see layering
and changes in color.

The lower part is yellow.
Then it turns into grey.

Looking closer to the texture
and structure of the deposit,

we can work out it's actually
made by several volcanic surges.

For the first 12 hours
of its eruption,

vesuvius throws gas and debris
into the air

until it towers 21 miles
into the stratosphere.

Northwesterly winds
blow it eastwards.

And herculaneum to the west
is initially spared.

During the night,
the ash tower collapses.

A surge of ash and hot gas
barrels down the volcano,

blasting its way
through herculaneum.

Five more surges
bury the town's buildings

in thick layers of material,

preserving structures, objects,
and victims almost intact.

This phenomenon is called
pyroclastic flow.

Why doesn't it simply
burn everything in its path?

Buongiorno. Ciao, ciao.

In his lab in rome,

guido sets up an experiment
to investigate this mystery.

We start with a piece
of fresh wood

from the herculaneum area,

which is the same species
of the carbon

that we find in the deposits.

He puts the sample

inside a heating device
called a calorimeter

to discover what happens
to the exposed wood

from herculaneum
during the eruption.

Usually we think that

wood can burn with flame
and oxygen in a fire.

But a pyroclastic flow
is a cloud of toxic gas.

There's no flame or oxygen,
so objects can't burn.

What we learned
is that if we heat up

to a very high temperature
with no oxygen,

this piece of wood,
it carbonizes.

But it maintains its shape.

In this fiercely hot
oxygen-free environment,

the wooden objects and furniture
turned to carbon.

A thick layer of ash
then sets around the town.

It insulates everything
in a protective layer.

It is thanks to these
unique set of circumstances

that we can learn so much
about roman life

even after nearly 2,000 years.

The catastrophic
eruption of 79 a.D.

Devastates the area

and instantly kills
the local population.

But at the same time,

vesuvius transforms herculaneum
into a frozen ancient wonder.

Vesuvius is a killer,

but does
its volcanic ash and debris

give life to another
roman wonder... pompeii?

A clue could lie
in the very fabric

of the city's ancient buildings.

Rome's greatest wonders
are iconic monuments

that champion the glory
of the mighty roman empire.

Pompeii...
Our seventh ancient wonder

is world famous
for a very different reason.

Also located near
the bay of naples,

pompeii lies just a few miles
along the coast

from neighboring herculaneum...

Another roman city
with its citizens

preserved beneath layers
of volcanic ash,

suspended for millennia,

and now miraculously
rediscovered.

The eruption of mount vesuvius

buries buildings
and boils brains.

The volcano destroys pompeii,
killing all who remain.

Yet vesuvius
once gives pompeii life.

Geologist guido giordano
investigates the city.

He wants to discover
how the people of pompeii

once benefit from the volcano.

Everywhere
you walk through this city,

you find evidence
of volcanic material

being used in construction,
and this is because volcanoes

produce a wide variety
of rock types from hard

and heavy lavas to soft
and light volcanic tuffs,

and in the bay of naples,
those are everywhere.

Pompeii's roman roads are laid
with tuff lava stone

to withstand the heavy traffic
of horse-drawn carts.

Decorative architectural
features are sculpted

from softer volcanic tuff.

Do these materials help pompeii
become a roman city of wonders?

Beneath a house in the south
of the city

lies evidence of pompeii's
original architecture...

Stone foundations
buried below the surface

that predate the surrounding
buildings by hundreds of years.

They stretch back
to the 6th century b.C.

Made from soft volcanic rock
and packed into the ground

a mere 4 inches deep,
these foundations are the roots

of the earliest structures
in pompeii.

Could this rock explain why
this city thrives?

In 79 a.D., vesuvius has been
dormant for hundreds of years,

but volcanic material
from much older eruptions

forms the region's bedrock.

Building materials
are fundamental

to understanding
ancient civilizations.

This material is actually
very soft, very easily workable,

but at the same time,
it is strong,

and that's why pompeii
is largely made

of blocks of tuff like this one.

The volcano provides the raw
material for early pompeians

to build their settlement,

but guido believes that when
the romans conquer this region,

their ingenious use of tuff

helps them
to supersize the city.

He investigates a stone mine

deep beneath the nearby city
of naples.

Here, ancient tuff can be found
in its original state...

Volcanic ash cemented into rock.

The citizens used
carved blocks of tuff

to construct pompeii's
grand public buildings,

but they also use it
as a mortar.

When crushed, the rock
turns back into loose ash.

One of the most revolutionary
invention of ancient romans

was to mix this volcanic ash
with quicklime

to produce a cement

that is actually able to dry
even in wet environments.

Like the discovery of
super strong mortar at baiae,

the development
of hydraulic cement

means romans not only build
wondrous super-sized monuments

and structures,

but now they can
also build underwater.

This invention allowed them
to build concrete structures

and piers for their harbors,

and this is probably
one of the key aspects

of the success of pompeii.

This local wonder material

transforms pompeii's influence.

The advanced infrastructure
of the bay of naples ports

enables pompeii to thrive.

Pompeii had a prime location,

so no wonder it was flourishing
in the 1st century.

Mighty vesuvius is clearly key
to pompeii's prosperity.

Pompeii is built
thanks to the volcano,

thrives because of the volcano,

and is devastated but ultimately
preserved by the volcano,

vesuvius is critical
to transforming

this seemingly normal roman city

into the iconic wonder city
we know today.

But the unique materials
it provides

isn't the only marvel here.

The wonder is what is preserved.

Astonishing discoveries
at neighboring herculaneum

provide archeologists
with unique insights

into ancient roman life.

Rome's ancient wonders
are incredible feats

of human achievement.

Iconic monuments that represent

astonishing engineering
accomplishment.

But the last roman wonders,

the twin cities
of pompeii and herculaneum,

are wonders
for a different reason

their citizens are cruelly
killed by vesuvius' eruption.

But the cities
are miraculously preserved

by the volcano's ash.

Two cities frozen in time,

buried beneath layers
of volcanic ash,

are the remarkable remains
of life in ancient rome.

But what secrets
does herculaneum conceal

that earns it a place
among rome's greatest wonders?

The city covers an area
the size of 30 football fields,

but 3/4 of it remains buried.

Andrew wallace-hadrill
is the director

of the herculaneum
conservation project.

He investigates the mysteries

hidden within
this preserved ancient city.

Herculaneum was destroyed
in the same eruption as pompeii.

But unlike pompeii,
the quality of preservation here

is quite exceptional.

Herculaneum is
a volcanic time capsule.

It is preserved in a flash,

burying clues
that can now reveal

exactly how remarkable
this city is.

Inside the buildings,

archaeologists discover
thousands of objects.

One of the rarest things
about herculaneum

is the survival
of wooden furniture.

Here we've got a bed,

wonderful sort of
chest of drawers,

and here's a very moving
thing... a cradle.

The baby was lying in the cradle
when they found it.

Today, archaeologists
still excavate the town

from under millions of tons
of volcanic ash.

In one corner,
an enormous villa emerges.

What we see here is the cliff
face of an enormous excavation,

and right down at the bottom
of it is the villa.

When the original
excavation starts

at the huge villa,

workmen carve narrow tunnels

into the thick volcanic rock
by hand.

After more than
two years of digging,

they break through into a room

with strange black cylinders
scattered on the floor

and on shelves.

Over 1,700 papyrus scrolls

baked black
by the heat of the eruption.

This is the only intact library
from the ancient world.

A monumental find.

What do these scrolls reveal

about herculaneum and roman life

that makes them so special?

The tunnels excavated
through the villa de papyri

are off-limits to most visitors.

Andrew has unique access
to explore

this claustrophobic labyrinth.

These tunnels
are still untouched

since herculaneum's
rediscovery in the 1700s.

This is the tiny room
in which the explorers

of the villa found hundreds
of rolls of papyrus.

They looked like
burnt lumps of coal.

Initially, they started chucking
them away until they realized

"no, this is something
much more precious.

There's writing on them."

What do the scrolls say?

And what can they reveal
about their owner?

These papyrus scrolls
are so blackened

that it's virtually impossible

to read the black ink
against the black paper.

Today, the fragile
scrolls are stored here

at the national library
in naples.

Papyrologist david blank
works to decode

these mysterious ancient texts.

Reading the papyrus
and reconstructing its text

and then making sense of it
has been the biggest challenge

that I've had
in my professional life.

To decipher them,

david uses a groundbreaking
technology created by nasa

called multispectral imaging.

It uses different wavelengths
of infrared light

to separate the ink
from the background.

Suddenly you could see
whole lines of letters and text

that you could actually
then reconstruct

into an intelligible
piece of writing.

So in essence, we're using
digital-age technology

to read something that was
written 2,000 years ago.

And that's really pretty great.

When david deciphers
the fragments,

he discovers that most
of the scrolls are written

by a greek philosopher.

It's a vital clue to the
identity of the villa's owner.

This philosopher had
a very important roman patron

who was piso.

And piso was also the
father-in-law of julius caesar,

and so a person
who can obviously afford

this extremely
luxurious establishment.

Julius caesar is one of the
most famous romans in history.

Rome's all powerful dictator.

His father-in-law's villa

is one of
the most magnificent ever found.

Andrew believes the discovery
of piso's villa

reveals herculaneum
as more than just a city.

It's one of the most
important cities in the empire.

In its present state,
you can only begin to imagine

the extraordinary size
and beauty of this villa.

This is rich at a global level.

This is a guy who was
father-in-law of julius caesar.

You don't get more important
than that in roman society.

Herculaneum is far wealthier
and important

than its more famous neighbor
pompeii...

Two cities captured in time
2,000 years ago,

insights into roman life
buried deep

now revealed
to an astonished world.

Pompeii and herculaneum cannot
match the colosseum for size,

the pantheon
for technical genius,

or the domus aurea for opulence.

But their preservation through
the power of vesuvius

makes them worthy roman wonders.

But could their deadly past
offer a clue

to what may happen
to rome's greatest wonders

in the future?

Hadrian's wall in britain,

the pont-du-gard aqueduct
in southern France,

and the pantheon
in the heart of rome,

these ancient wonders exemplify
the absolute best

of roman ingenuity and design.

Excavations at sites
across the empire

continue to this day,

revealing stunning new evidence
of this ancient civilization.

But they also give us a glimpse

of a possible
devastating future.

One day, could all of rome's
ancient wonders be buried again?

Volcanologist
giuseppe mastrolorenzo

investigates mount vesuvius.

He's trying to figure out
whether the volcano

offers any warning of the fury
it unleashes.

But the volcano that towers
above the bay of naples today

is a vastly different mountain

to the one that exists
2,000 years ago.

Vesuvius has erupted more
than 30 times

since it consumes
the twin cities

of herculaneum and pompeii.

Giuseppe and his colleagues
at the vesuvius observatory

watch the mountain
for signs of it stirring.

It's not just vesuvius

that threatens
the modern gulf of naples.

A ring of volcanoes
surrounds the bay,

including europe's largest,

campi flegrei.

If campi flegrei or vesuvius
erupt again,

it will be a devastating
catastrophe.

So despite the warning
from history,

why, today, is
the volcano blast zone

more populated than ever?

Volcanoes provide a wealth
of benefits at all times

and occasionally severe hazards.

The people of the east region

have learned to be resilient,

to cope with
the volcanic hazard.

Vesuvius and the region's
other volcanoes

still pose a threat.

It's almost inevitable
that one day,

they will erupt again.

When that happens,
the ancient wonders of rome

are as likely to survive

as the buildings
of modern day Italy.

Thanks to the empire's
engineering excellence

and its ingenious use
of super strong concrete,

rome's finest monuments

have endured
the ultimate challenge...

To withstand the test of time.

After the great civilizations

that craft the seven wonders
of the ancient world,

the roman empire surpasses
the size, scope, and ambition

of the original marvels

and raises the bar

for the ultimate
achievements of humanity.

By building smarter,
stronger and longer,

the romans defeat their enemies
and conquer new lands

to expand their empire

and build seven ancient wonders

that helped to define

the greatest civilization
on earth,

ancient rome.