Wild Castles (2017–…): Season 1, Episode 1 - Heidelberg: Secrets in Stone - full transcript

In the heart of Germany

stands one of the most iconic
sites on the continent...

...Heidelberg.

A castle, once glorious
beyond compare, now in ruins.

As Europe emerged
from the dark ages,

the most brilliant light
of learning

emanated from this city.

The vibrant river and mountains
teemed with wild creatures.

Animals beckoned
to scientists and physicians

as subjects
for study and inspiration.

But new ideas about religion



soon pitted Protestant
against Catholic,

sparking a war
that would tear Europe asunder,

and reduce
the great castle to rubble.

Amidst human tragedy,

the animals managed
to adapt and even thrive,

writing a new chapter
in the history of Heidelberg.

WILD CASTLES - SEASON 1
EP - 1 - Heidelberg: Secrets in Stone

Heidelberg Castle was once among

the most majestic sights
in Europe.

The sunny slopes of the
surrounding Odenwald Mountains

provided unsurpassed
natural bounty.

At the foot of the castle,

the River Neckar
linked Heidelberg

to the mighty Rhine
and to the world.



Powerful rulers here served
the Holy Roman Empire.

They turned Heidelberg
into the foremost center

of learning in Europe.

In every direction,
nature's living laboratory

offered up a wealth of plants
and animals to be studied.

A new era of science blossomed
in a most unexpected place...

...the Church
of the Holy Spirit,

just a stone's throw
from the castle

in the heart
of old-town Heidelberg.

Today the church watches over a
different kind of new beginning.

Peregrine falcons
had nearly disappeared

by the end of the 20th century,
victims of pesticide exposure.

But the birds
are making a comeback,

and they've found
an ideal breeding place...

...in the church bell tower.

Three new chicks
have just emerged.

Their parents take turns
gently sitting on them

to keep them warm.

It will be 42 days

until they're big enough
to leave the nest.

Until then,
the parents will provide

a steady stream
of pigeons and doves,

and round-the-clock care.

Beneath the bell tower nursery
lies the birthplace

of the very first
university in Germany,

now more than 600 years old.

Founded in 1386,

the young school soon became

a center of philosophy
and medicine.

The church coffers
provided funding,

and its halls offered
space for research.

After centuries
of the Dark Ages,

the light of science
and medicine

at last shined in Heidelberg.

Like those early academics,

the young peregrines
have plenty to discover

in the surrounding landscape.

Rich hunting grounds
are right on their doorstep,

just beyond the castle ruins.

As the male leaves
in search of food,

he heads southeast
to the foothills

of the Odenwald Mountains.

Odenwald means
"forest of legends."

Today it's a 1,000 square mile

nature preserve,
the perfect place

for a legendary hunter
to return.

Beneath the canopy are many
of the same plants and animals

that were here 600 years ago.

Heidelberg's early physicians
sought them out,

walking this
forest to find ingredients

for their concoctions and cures.

This male European toad
has just emerged

from a state
of suspended animation.

It spent the winter buried
underground, as still as death.

Then, when nighttime
temperatures rose

to around 40 degrees Fahrenheit

and a rejuvenating rain
soaked the earth,

thousands emerged en masse.

His singular mission is
to get to the breeding pond,

the same one he was born in.

To get there, he'll cover almost

half a mile a day.

The going gets tough,
but he can't afford to be late.

En route, the male keeps
a lookout for a female.

If he finds one,
he'll hop on board

and let her carry him
the rest of the way.

She's bigger,
but in addition to carrying him

she's hauling thousands
of unfertilized eggs

in her abdomen.

Finally,
their goal is in sight...

...not a woodland pond,
but Heidelberg Castle.

The castle's
spring-fed fountains

are one of the most important
amphibian spawning grounds

in the region.

This may look like
traditional mating,

but actual fertilization
happens in the water.

She lays a string of eggs,

and from his prime position
on her back,

he fertilizes them
as they emerge.

They'll swim together
for up to 12 hours

stringing yards
of fertilized eggs

among the aquatic plants
and branches.

A jelly-like substance
forms a protective cover

around the eggs as they develop.

These grass frog eggs
operate on the same principle,

only they're arranged in
a cluster instead of a string,

providing
a little more protection.

The outermost eggs
remain vulnerable,

and a little alpine newt
has decided

that one would make
a very nice meal.

Fortunately, there are
a few thousand left.

These days, the frogs and toads
can get on with mating here,

unmolested by humans.

In the 15th century,
they didn't have it so good.

Amphibians like them were
raw materials for medicine

that was supposed to impart

their animal abilities
to humans.

Their moist, permeable skin
was the charm.

Salamanders were boiled alive

to make lotions
for treating burns.

Frogs were cooked in sesame oil
to cure arthritis and gout.

Such ideas might seem
ludicrous today,

but many modern drugs

are derived from chemicals
in frogs' skin.

A line can be drawn
from modern pharmacology

directly back to these
first laboratory kitchens.

While knowledge grew,
the old power of mythology

and symbolism
still influenced science.

For inspiration,
physicians turned to Asclepius,

the Greek god of medicine.

Wrapped on his staff

is one of the most enduring
animal totems in medicine...

...the snake.

The ability to shed its skin

was to scientists of the day
nothing short of rejuvenation,

the ultimate healing power.

Heidelberg's local serpent
is a rarity.

In Germany, the Aesculapian
snake only exists

in three isolated areas,

one being
the Odenwald Mountains.

At almost six feet long,

it's the longest snake
in this country.

It keeps its head up
while cruising

to see its surroundings

and pick up scents
with its forked tongue.

Mice and other small mammals
are its favorite food,

but it won't turn up its nose
at lizards or amphibians.

It's also an excellent climber,
so even birds aren't safe.

When it finds prey,
the snake kills by constriction,

as it lacks the venom

that has fascinated
scientists for centuries.

Fortunately, modern science
no longer condemns snakes

to the apothecary's pot.

But their appearance as a symbol

of the medical profession
endures.

As the 16th century dawned,

science at Heidelberg
had already progressed

by leaps and bounds.

The Book of Medicine,
written here,

was the most comprehensive work

of medical science in its time.

Its thirteen volumes
contain over 18,000 remedies

and medicinal plants,

many of which
are still acknowledged today.

Its creator was none other
than Heidelberg's Louis V,

who ruled the city
during the early 16th century.

It took him more than 20 years
to write these books by hand.

When he wasn't writing,

Louis V was busy overseeing

a massive expansion project.

He enlarged the castle's library

to fit the ever-growing
number of books.

More construction followed.

Details of this architecture
point to his love of nature.

Like the physicians,
Heidelberg's architects looked

to the surrounding natural
world for inspiration.

They didn't have to look far.

Right below the castle
flows the Neckar River.

It's home to an animal
that inspires all builders...

...the beaver.

Like Louis V and his forebears,

this family of beavers
has built its stately home

over many generations.

Last year's offspring are
almost as big their parents.

These kits will continue
to live in the family keep

for around two years,
before striking out on their own

to become the architects
of a brand new wetland.

Since beavers spend much
of their lives in the water,

it's critical that
they're well waterproofed.

They spend hours grooming
and oiling their fur.

Glands between their back legs

secrete an oily substance
called castoreum,

which they meticulously
comb through their fur.

This substance made beavers

a target of Heidelberg's
burgeoning medical science.

Physicians extracted
the castoreum from these glands

to use as a remedy
for everything

from ulcers to fevers,
to cramps and rheumatism.

The secret to its
healing properties

lies in the beaver's diet.

Willow bark
contains salicylic acid,

the raw ingredient of aspirin.

The waterproofing castoreum

contains high levels
of this compound.

For the beavers, though,
willow branches are just food.

They can grow to up to 66 pounds

eating little else.

Their teeth are specially
designed for the job,

coated in a hard layer
of red iron oxide.

As a beaver's teeth
grind over each other,

they sharpen to a blade.

Wood that's too tough to eat
becomes building material.

Beavers use the water
to transport big willow boughs.

It's much easier and safer

to float and swim
than to drag them over land.

Moving goods
up and down the river

was key to the growth
of Heidelberg as well.

14 miles downstream,

the River Neckar
flows into the Rhine,

one of Europe's
most important trade routes.

Spices and exotic plants
from all over the world

made their way
upriver to the city.

On the opposite bank
from the castle,

non-native plants found a
surprisingly favorable climate.

The southern exposure
of the Odenwald Mountains

makes this one of
the warmest regions of Germany.

Mediterranean plants
that are seldom found

north of The Alps thrive here.

Almond, peach and apricot trees,

even pomegranates
bear fruit here.

Terraced orchards
divided by stone walls

make the most of the sunshine.

Warm-weather creatures
take advantage as well.

Sand lizards and
more common wall lizards

dwell in the many
cracks and crevices.

As cold-blooded reptiles,

they can't internally regulate
their body temperature,

so they have to live somewhere

with both warming sunshine
and cooling shade.

Their scaly skin keeps them
from losing moisture.

But as this sand lizard grows,
he needs to replace his jacket.

This sloughing of skin
happens many times a year.

To ease the itch
and help the process along,

the lizards make good use
of the rough stone walls.

The stones are
also a great place

to soak up the morning
sun after a chilly night.

Once the lizards
have warmed up their muscles,

they can head out to hunt.

Cocking their heads,
they scan the surroundings.

With so many flowering trees,

insects are never
in short supply.

It's all a matter of
being quicker than the bug.

There are always surprises.

An ant puts up a valiant fight
over this grasshopper.

A risky move
against a hungry sand lizard,

but it makes off with a morsel
to bring back to the nest.

Among the many flowering trees,
one bug reigns...

...honeybees are
crucial pollinators.

A new colony
is setting up a nest

in one of the terrace walls.

With their queen protected,

they get to work building
a nursery of honeycomb.

They glue their structure
together with propolis,

a mixture of plant oils, sap and
wax fermented with bee saliva.

It has the added benefit

of protecting the surface of the
nest from bacteria and fungi.

In the field of pharmacology,

Heidelberg's bees were way
ahead of its human scientists.

Nursery ready, the queen
begins to lay her eggs,

depositing one into each cell.

Now it's up to the youngest
bees to care for the larvae,

all of which are female.

After 21 days,

they welcome their new
sister bees into the hive.

The sunny south-facing bank
of Heidelberg

doesn't just appeal
to plants and animals.

Students from the university
once came here

to stroll and ponder
life's questions.

Today the place is still known
as the Philosopher's Way.

Nature was a place for
reflection and contemplation.

The place for serious research
was back across the river.

The Church of the Holy Spirit

had been the birthplace
of the great university.

Now it assumed a new role

as the biggest library
of the Renaissance in Germany.

The vast galleries were filled
with books that represented

the best available knowledge
on all subjects.

The brightly-lit rooms
were perfect for reading.

One of the most
cherished manuscripts

was "The Art of Falconry,"

written by
the Holy Roman Emperor

Kaiser Frederick
himself in 1248.

It's considered
the first work of zoology

written in the spirit
of modern science.

In Heidelberg's golden age,
people raided falcon nests

for chicks
to hand-rear for sport.

Today, the three chicks
living in the church bell tower

have no such problems.

They can take in
the best view of the city

while waiting for their mother
to return with food.

Six weeks have passed
since they hatched.

Their fluffy down has given way
to proper feathers for flight.

Instinct tells them to flap,
but these two chicks

don't have the confidence
for take off just yet.

Their brave sibling, though,

has already made it
to a nearby rooftop,

just in time to miss
the food delivery at the nest.

The others are waiting eagerly

as their mother returns
with a pigeon.

But there's no reward
for being timid.

She pulls the meal
back to the window.

If they want to eat,

they'll have to step
out of their comfort zone

and take a leap of faith.

The brave chick tries
to catch up with its mother.

But landing on the steep tower

is a tough maneuver
for a first outing.

It's a big day
for the young falcons,

as they change from nest-bound
chicks to fully-fledged adults.

In the early 1600s,

a fledgling prince struggled

with the sudden ascent to power.

Frederick V was only
14 years old

when he assumed
the rule of Heidelberg.

The young Prince found himself
on the cusp of history.

The Protestant Reformation

had been gaining
influence in Germany

and Heidelberg had
become a Protestant city,

ruled now
by a Protestant prince.

Tensions with the Catholic
Church in Rome were on the rise.

But the young ruler's reign
was also in danger

on another front closer to home.

By the age of 18, he began
to suffer from strange fevers.

Heidelberg's best doctors
claimed that foul odors

from swamps along
the River Neckar were to blame.

They weren't too far off.

It wasn't the swamp air, but
the mosquitoes that bred there.

Today we think of malaria
as a tropical disease.

But in the early 17th Century,

mosquitos carrying
the malaria parasite

existed well into
the temperate zone.

The mosquitoes still persist
in Heidelberg's wetlands today,

but they no longer
carry the disease.

Tiny rafts of mosquito eggs
float on the stagnant surface

of one of the Neckar's
small tributaries.

The islands are only
the size of a grain of rice

but hold between
200 and 300 eggs.

Underneath, the larvae
have already begun to hatch.

They continually filter-feed

microscopic plankton
from the water.

They breathe
through their tails,

which poke like snorkels
through the surface film.

They'll shed their skin
three times as larvae,

growing larger each time.

On the fourth shed,
they become pupa,

with recognizable wings
and eyes.

From the pupa,
they emerge as adult mosquitos

to break the water's surface.

It would take doctors
almost three more centuries

to trace malaria to mosquitoes.

Prince Frederick's doctors
held to the belief

that foul air was to blame.

The word "malaria"
literally means "bad air."

And the best way
to combat bad air

was with
pleasant smelling fragrances.

The doctors of Heidelberg
gathered bundles of flowers

from the Odenwald Mountains
to treat the ailing prince.

They dried the flowers
and infused them in oil

to concentrate their fragrance.

Today the practice
is known as aromatherapy.

The blossoms may have eased
young Frederick's fever,

but he remained sickly and weak.

When he wasn't suffering,
he sought solace in nature

and a blossoming love for
his young wife Elizabeth Stuart,

the English King's daughter.

To honor her,
he built the Elizabeth Gate.

This declaration of love

is covered in images
of tiny natural wonders.

To complement the gate,

he commissioned
a French engineer

to lay out a sumptuous garden.

At the time of its creation,

many considered it
the eighth wonder of the world.

It was to be the embodiment
of creation itself,

a veritable Garden of Eden.

He planted such
a variety of flowers

that there would be blooms
every month of the year.

He built balconies
to overlook the splendor,

secret grottos, and
elaborate spring-fed fountains.

The very fountains that today
are a haven for amphibians.

These alpine newts are having
their annual spring mixer.

The males are spruced
up for the occasion.

Their normally drab skin has
turned bright and iridescent.

The females keep their
usual brownish-grey attire,

but their bellies swell
with unfertilized eggs.

The male's dragon-like crest
is enlarged,

as is his cloaca,

the reproductive opening
at the base of his tail.

Competition is fierce.

Not all will find a mate.

The sense of smell plays
a big role in courtship.

Although newts breathe air,

an organ in their mouths
can detect smells underwater.

That way he can tell
if she's ready for wooing.

The time is right,
so he vibrates his tail

to show he's ready,
and that seals the deal for her.

Many other creatures rely on
the fountains for reproduction.

Fire Salamanders
have already mated,

but the females need these pools

to give birth
to their live larvae.

There's an unexpected problem.

Amorous male toads
fresh in from the forest

are looking for mates.

They'll latch on
to anything that moves.

The salamander mother
is undeterred.

One by one, her babies emerge
in their protective sacs.

As each one drifts
to the bottom, the sac bursts

and a fully developed
larva emerges.

After a moment
to recover from the ordeal,

it's ready to swim and feed.

For now, it breathes
through feathery gills.

Most other amphibians
begin as fertilized eggs.

Being born as a group
offers some protection.

The toad tadpoles
also have gills.

The cold, oxygen-rich water
is perfect in this larval phase.

But the transformation
to terrestrial animals

has already begun.

Each species proceeds
in its own particular way.

The toads' gills retract
and become internal;

meanwhile,
they're developing lungs.

Grass frog tadpoles are
already growing hind legs.

Alpine newts still have
external gills,

but they already have
all four legs.

Such rapid development
requires a lot of fuel.

A veritable banquet
of water fleas,

worms, and insect larvae
does the trick.

New fire salamanders
are just as voracious.

They're already getting
their adult spots.

Each pattern is unique,
like a fingerprint.

Every species follows
a different schedule,

but the moment of transformation
eventually arrives for all.

Young toads break their watery
confines and step onto land.

Tadpoles no more,
they look almost identical

to their parents...

...only a lot smaller!

When you're that tiny,
everything is an obstacle.

But soon the tables will turn.

In 17th-century Heidelberg,

a big transformation
was also underway.

A storm was brewing over Europe,

the likes of which
no one had seen.

The Holy Roman Empire
was determined

to enforce Catholicism
in all its territories.

Heidelberg stood
in direct opposition.

The ideas that fueled
the Reformation

flowed from
its Protestant chapel.

Frederick V,
the young, sickly prince,

pledged to defend
the Protestant faith.

Under pressure from his allies,
Frederick traveled to Prague

to be crowned
the Protestant king.

His reign would be so brief

that history now calls him
"The Winter King."

The Catholic League
answered this provocation

with full military might.

In 1620, Frederick's forces
met the Catholic army

on the banks of the Vltava River

in what is now
the Czech Republic.

The Protestant troops were
annihilated,

and Frederick fled into exile.

Still, the Catholic forces
were not satisfied.

They wanted to root out
the Reformation at its core.

So they took aim
at Heidelberg itself.

Fear spread through the city.

People saw omens
in the natural world.

Common swifts, seeming
to appear out of nowhere,

like a vast winged army,

were believed to predict
bad things to come.

Their unsettling cry earned
them the name "screech devils."

But these spring migrants

were merely harbingers
of fair weather.

Swifts live
their lives in the air.

They can stay in the skies
for months without landing.

They do almost everything
on the wing.

But they have to land
to nest and raise young.

Every year,
they make the journey

from the Sahara Desert
to Germany.

They're drawn to rocky cliffs
and, since it's destruction,

to the old battlements
of Heidelberg.

A hole in an old turret
is the perfect spot.

The castle walls
are well occupied.

While the swifts have the turret

and the falcons
are in the belfry,

a family of common kestrels
has claimed an arrow slit.

The parents patrol constantly,

scoping for enemies or prey.

Kestrels hover in mid-air
to scan the ground below.

Their sharp eyes can detect the
faintest movement in the grass.

Thanks to their parents'
hunting skills,

the chicks don't have
to wait long to be fed.

In the castle tower next door,

the five-week-old swift chicks
have grown their adult feathers.

Only their white faces
betray them as youngsters.

In just another week,

they'll be making
their first trek to Africa,

not coming to rest until
they have chicks of their own.

No other bird spends as much
of its life on the wing.

Adult swifts that haven't
managed to breed this year

aren't caught sitting still.

In the evenings,
they organize into huge groups

called "screaming parties."

Together they climb to heights

of between 6,000 to 9,000 feet.

They'll spend the entire night
circling high above the castle.

They can even sleep on the wing

by shutting down
half their brain at a time.

On mild summer nights,

hundreds of pipistrelle bats

swarm through the battlements.

It's thought that the adults
are showing their offspring

the best places for
hibernation when winter comes

in a few months' time.

Ounce-for-ounce,
the common pipistrelle

is one of the world's
smallest mammals,

weighing little more
than a sugar cube.

When its wings are folded,
it's smaller than a matchbox.

The pipistrelles
share the castle walls

with larger mouse-eared bats.

Up to a thousand
congregate here.

They spent winter tucked
deep into the battlements,

slowing their metabolism
and living off of fat stores.

Now that it's warm,
they're active,

nabbing as many bugs as they can
while the pickings are good.

Whatever the season,
the castle walls provide

all the protection
the bats need.

The same could not be said

for the 17th-century
citizens of Heidelberg.

Frederick V had put his effort
into lavish gardens

at the expense
of strong fortifications.

In July 1622, the Catholic army
crossed the River Neckar.

For 11 weeks,
they laid siege to Heidelberg.

On the 19th of September, 1622,
the city fell.

The Catholic army

razed Heidelberg Castle
and city to the ground.

The exiled Frederick V
never returned home.

The ensuing Thirty Years' War

between Protestants
and Catholics

tore Europe apart.

Entire regions lay in waste.

Plague and starvation
took an even greater toll.

But few places suffered
more than Heidelberg.

Frederick's magnificent gardens,

once considered
the eighth wonder of the world,

lay in ruin.

The precious library,

one of the greatest
seats of learning

Europe had ever known,
was dismantled.

The victorious Catholics
sawed church pews

into chests for transport

and shipped the university's
treasured collection of books

to Rome as a gift to the Pope.

For many years,
the castle remained uninhabited.

In Heidelberg,
the Reformation was over.

The city was Catholic once more.

The young peregrine falcons

are undergoing
a conversion of their own.

They've left their home
in the Protestant Church

of the Holy Spirit
and have come to rest

on the nearby Jesuit Church.

From here, they make
daily trips into the forest

for intensive training.

As the world's fastest birds,

they'll soon be
dive bombing their prey

at up to 240 miles per hour.

But they have to learn
how to harness all that speed.

Mother tempts her offspring
with a piece of food.

All three youngsters join
in the game of keep-away.

It's all in service
of perfecting

the high-speed maneuvers
that will keep them,

and their future families,
well fed.

One day, mother and father
won't show up with food.

The young falcons
will be on their own.

40 years after
the fall of Heidelberg,

a precocious youngster was also
stepping out into the world.

A young girl named Liselotte,
granddaughter of Frederick V,

brought a ray of hope
to the beleaguered city.

She was a boisterous child
who loved to play in nature.

In the spirit
of Heidelberg's past,

she was a budding scientist,

who is said to have kept
snakes in her room.

But the times were against
the curious Liselotte.

In the mid 17th century,

the field of science was
off limits to women.

Instead, Liselotte was married

into the court of Louis XIV
of France.

Her family hoped
that the marriage

would inspire the powerful
Catholic Sun King

to protect their homeland.

They were wrong.

In 1688, French troops invaded
and once again destroyed

the city of Heidelberg.

Citizens were burned alive
in churches

and the city was razed
yet again.

Liselotte could do nothing
to stop the carnage

and blamed herself.

She wrote,

"All night, as soon
as I fall asleep a little,"

"I see all the destruction."

"And then I drift
and cannot sleep again."

"I lament that I am the downfall
of my fatherland."

In the years that followed,
the once great city

fell into a fairy-tale sleep
among the ruins.

But in the rubble of lost glory,
animals found a haven.

The castle that could not
protect its people

now succeeds in protecting
its wildlife.

Almost by accident,
Heidelberg has again become

a living laboratory
of natural science.

In its own way,

living up to its promise
from centuries ago.