Underground Marvels (2019–…): Season 1, Episode 7 - Jersey War Tunnels - full transcript

The underground bases built by the German army during the occupation of Jersey, and a group of more than 20 underground cities in Turkey, one of which dates back to 800BC.

Narrator: In world war ii, why did
hitler convert the channel islands

Into an invincible, underground fortress.

Talking about solid
granite, it took a lot of work.

Narrator: How did a
little-known ancient civilization

Use this labyrinth to wage a guerrilla war

Against their powerful
and aggressive neighbors?

And how have two underground marvels

Transformed the fame and fortune of a city?



Beneath our feet lie
extraordinary chambers,

Caves, vaults and tunnels...



The span and the size is just crazy.

Narrator: ...Some designed
and built by humans.

Others formed over thousands of years,

But how were they created and adapted?

By whom, and why?

You've got to face your fears.

Narrator: Throughout
history, subterranean life

Has captured our imagination.

We've going further and
deeper to unearth the mysteries,

The stories and the secrets
of underground marvels.

25 miles off the coast of France

Lies the archipelago known
as the channel islands,

But surprisingly they don't
belong to the european mainland.

They are proudly british territories,



And the largest of them is jersey

With an area of 46 square miles.

During world war ii, the
islands were occupied

By nazi forces under
orders from adolph hitler,

But why did the fuhrer
take such an interest

In this tiny land mass?

Working for the germans
was, really, something

That nobody really want to do.

Narrator: What did it
take to convert the island

Into an impenetrable system
of underground bunkers...

Jersey was the most
fortified place in the world.

...And at what cost?

So where did they get all this labor from?

They brought it in.



Narrator: Similar to the status
that puerto rico holds in the us,

The channel islands
are dependent territories

Of british.

While not technically part of the uk,

The residents self-govern
yet are british citizens,

And from September 1939 to spring 1940,

Jersey and the other channel islands

Were largely untouched by world war ii.

But by June 1940,

Following the german
defeat of the allies in France

And their evacuation from dunkirk,

The british government determined

That the channel islands
had no strategic value

In the war effort.

The decision was made
that they would not be

Defended by allied forces.

Marc yates, a battlefield guide,

Is an expert on jersey's military history.

Yates: What little
british military resources

Were here were taken off,

And then there was a general evacuation

Of the population of the islands.

Narrator: The population of jersey
prior to the evacuation was 50,000.

Nearly 7,000 residents decided to leave,

While 43,000 stayed behind
to face the nazis alone.

Code-named operation green arrow,

The germans quickly moved
in to occupy the islands.



Yates: It was british territory.

Although hitler never came here,

I think he got a bit obsessed by it,

And so at that point, they
organized operation green arrow.

The purpose of the operation was to occupy

The channel islands as part
of the occupation of France.

Narrator: The german
air force, the luftwaffe,

Landed on jersey on June 30th, 1940,

And the island's government
surrendered the very next day.

The arrival of the germans
and being under occupation

Must have been pretty scary at the outset,

And the unknown, you know, must have been,

You know, really, quite worrying,

Particularly for families
where you had young children.

Narrator: There aren't many residents

Remaining who remember the invasion,

But trevor green, now 82, was just a boy

When the germans marched
into town by the thousands.

Green: When I was about 5,

And I first came into
contact with the germans,

Where I lived, at a place
called millard's corner.

Narrator: Hitler anticipated
that the allies would attack

His european-held territories,

So he fixated on the
creation of a defense system,

Which he called the atlantic wall.

It was a series of fortresses,

Gun emplacements, tank
traps and other obstacles running

For nearly 1,900 miles along the coast.

As part of the directive,
the germans turned jersey

Into a fortress of bunker systems,

Housing radar and observation units.

They also planned nine
ocean-facing artillery posts

Like this one at battery moltke
in the northwest of the island.

The gun emplacements sit above
a network of bombproof tunnels.



Trevor green has reached out to tony pike,

An expert on jersey's military
history to better understand

What the nazis devised
underneath his homeland.

This is actually constructed
by making a deep trench,

Which would have been about
4 meters deep in excavation,

And once they've actually
done their excavation,

They would have poured the floor.

Then they would have made
the shuttering for the walls,

Which you can still
see the imprint of today,

And once they've done
all that wooden shuttering,

They then poured the concrete behind,

And then they would have
done the shuttering for the roof,

Poured the concrete on top of that,

And then all the infill,

Which have been excavated
from the trench itself

Would have been put on top of that.

Around the tunnel.

The structure at battery moltke

Was built from concrete and steel,

Most of which had to be
shipped in from France.

The battery included underground bunkers,

A shelter for 27 soldiers and
four ammunition stock rooms,

Which served the gun emplacements

Situated above ground.

Excavating this vast
network was challenging.

Talking about solid granite,
and to mine it, to actually,

You know, create an excavation
4 meters deep and more,

It took a lot of work.

Quite a lot of blasting as well gelignite,

But they also used a lot of manual labor.

The 43,000 residents of jersey

Who remained after
the evacuation stood firm

And refused to help the
germans in this endeavor.

The channel islands being proudly british,

Working for the germans
was really something

That nobody really wanted to do.



Narrator: But the nazis were
determined to militarize the islands,

So they found a labor
force that couldn't say no,

And their brutal treatment

Which just one of the many
prices of hitler's war machine.



Narrator: When the nazis
invaded the channel island of jersey

In world war ii,

They started building artillery
posts like battery moltke

In the northwest of the island,
but they needed a workforce

To build hitler's vision of
an atlantic wall of defense.

Battery moltke and the
other installations on the island

Were constructed mostly by prisoners

And conscripts who were treated as slaves.

The men were brought in
from nazi-occupied territories

All over the continent.

Yates: They came from the
eastern front, from eastern europe.

They were typically soviet civilians

Who were conscripted
or soviet prisoners of war.

There was hundreds of
thousands of these people

That the germans used
as labor across europe.



Narrator: Locked up in nazi
camps across the channel islands,

A workforce of 16,000 was treated brutally

And forced to work in
treacherous conditions.

The germans reserved
the harshest treatment of all

For central, southern,

And eastern europeans
who spoke slavic languages.

Yates: The nazi party racial views

Regarded the slavic races as subhuman.

They were brutally treated, and, of course,

In an environment where you're starved,

You're not in the best of health,

And you're working on construction sites,

Where, to be honest,
there's no health and safety.

Narrator: In jersey alone,
over 6,000 forced laborers

Worked more than 12 hours a day.

Under constant fear of falling rock,

They excavated 1,000 yards
of tunnels through solid granite

Using only simple picks and shovels.

Pike: The forced workers
and the slave workers

Actually built this site.

That's very important to
remember what they did.

You know, it's a colossal amount of work

They did in all sorts of different weathers

With very poor equipment a lot of the time.

Slave worker, what they
had for protective clothing

Was an old cement
sack with a couple of arms

Just punched through.

Narrator: Due to cement
shortages in the summer of 1943,

The germans abandoned their original plan

To build nine batteries on jersey.

Only four army and two marine batteries

Were ultimately completed,
including battery moltke,

Which contains a gun emplacement,

Ammunition stock rooms,
and a gas-locked chamber,

All connected by tunnels 13 feet deep.

This personnel shelter was actually made

To be contrary against gas attack

Because hitler was
gassed in the first world war.

Mm-hmm.

He didn't want his troops to
go through the same experience,

So a lot of engineering

And thought has actually
gone into this bunker.

This part here, we're standing
underneath the showerhead,

So if there had been a gas attack,

This was a decontamination zone,

So the idea was you have the shower here,

And then you would go into this part,

Which would have been already closed.

Then you can walk straight
through here into the bunker.



In the event of a mustard-gas
attack by the allied forces,

These steel doors would
be locked and sealed

While pumps would
filter our poisonous gases.

This part of the bunker,
the air would be cleansed,

Filtered.

When a green light shone
that was placed up there,

Shone, then it was safe to open this door

And enter into the
main part of the complex.

At the heart of the bunker
are the filtration pumps,

Designed to keep the nazi
soldiers safe from lethal gases.

Air from above the
cliffs would be pumped in

Through a network of pipes

While carbon filters cleaned
the air making it safe to breathe.

I see it's got a handle. What is that for?

Well, if there'd been
an electrical failure,

Although battery moltke had
it own generation and plant,

That should say, for example,

If there'd been a bomb that hit it

And it had been disabled
for some reason or other,

And there had been a gas attack,
there's always a backup plan.

You could actually
crank this round by hand.

Because hitler decreed
that 10 percent of the steel

And concrete used in
the entire atlantic wall

Should go to the channel islands,

They ended up as the
most heavily fortified region

Along the nazi coastal frontier.

Tony pike believes the
efforts of the forced laborers

And this little-known nazi
occupation over britons

Shouldn't be forgotten.

When I was a 15-year-old lad,

I came down here for the first time,

And we came through one of the entrances,

Which we had to dig out by hand.

This is one of the ready
entrances for the crew

That would have gone out to man the gun,

And at the time, the rubble
was virtually up to about here,

Up to the roof.

We come down, and we
literally passed out all this rubble

By hand up into a skiff above.

Narrator: In addition
to the coastal batteries,

The germans built numerous tunnels

And bunkers across the channel islands,

Even a hospital for
their expected casualties

In the event of counter invasion.

Work is ongoing to
restore these underground

Mazes to remind the world of
what almost happened to britain.

This naval battery,

Known as a type fl 242 antiaircraft bunker,

Was just excavated in 2016.

Tony and the team were
surprised to find human touches

Added by the nazis.

Pike: When I first came in here,

The first thing I saw was the flowers.

When you look at the
detail, it's quite amazing.

They must have really wanted
to make it feel like home.

Narrator: When the war ended
in 1945, the liberated residents

Wanted their home cleansed of
the taint of german occupation.

The british army had the complicated task

Of removing more than 60,000 mines

And 30,000 tons of ammunition,

While the guns of battery
moltke were thrown over the cliffs.

In the decades that followed,

The abandoned bunkers
were used as dumping grounds,

But with the help of volunteers like tony,

Jersey's complicated
past and the tireless efforts

Of thousands of enslaved
workers will not be forgotten.

Green: When you think this
was worked on by the forced labor

And the slaves to build it,

And to achieve this, this
was a lot of hard work.

This bunker complex is quite incredible.



Narrator: Turkey is a stunning country

Bridging europe and the middle east.

Over its breathtaking terrain,

This land has seen much
bloodshed over its history,

Although not always above ground.

Dating back to the 8th century bc

Is an underground marvel

Hidden beneath the
central region of cappadocia.

Famous for its pockmarked
landscape of volcanic rock

Called tufa, this compressed volcanic ash

Is the site where two ancient civilizations

Came head-to-head in
combat 3,000 years ago.

How were these secret,
underground spaces engineered?

There are no straight lines,
no rational decisions made

By an architect or a constructor.

Narrator: And how have these tunnels
been adapted over the centuries?



Narrator: Kaymakli is
nearly 200 miles southeast

Of turkey's capitol, ankara.

The sprawling hill town
conceals numerous entrances

To a hidden world, a subterranean labyrinth

That has existed for millennia.

Built on eight levels, 130 feet deep,

Kaymakli has space for 5,000 people

To survive somewhat
comfortably for months at a time.

Husam suleymangil, a long-time guide,

Knows the tunnels intimately.



But who created this
cavernous realm, and why?

The evidence is illusive.

Despite the uncertainty,

Historians have estimated
kaymakli dates from 800 years bc

Based on artifacts found
in the surrounding region.

In the same era that
tribes of western europe

Were learning how to make
the first bronze age tools,

It's thought the people
living here in cappadocia

Were developing a network
of underground fortresses

To invade and entrap their enemies.



An ongoing battle was playing
out between the local phrygians

And the powerful invading assyrians.

The assyrians had
dominated the middle east,

And their empire had
lasted almost 2,000 years,

Ending around the 6th century bc,

While the phrygians
residing in central turkey

Were more closely connected
to the mediterranean civilizations.

Known for their legendary king midas

With the golden touch,

They built underground
cities like kaymakli to both hide

From and retaliate against
the aggressive assyrians.

The clever phrygians had a
plan in store for their assailants.

After making their enemies vulnerable

In this confined space,

A network of traps would lock them in.

Circular doors carved from rock

Were designed to roll into place
and block the tunnel entrances.

In the event the assailants

Couldn't be contained or pushed back,

The phrygians built
one final line of defense:

A secret passage hidden
within this underground marvel.



Narrator: The ancient hill
town of kaymakli in turkey

Was built to protect its
residents from invading armies.

It is ingeniously linked to
other underground cities

In the central region of cappadocia.

Suleymangil: They also have escape
routes, and they would just run out,

And some of those underground cities

Are connected to each other with,

Oh, about 6, 7-miles-long tunnels,

So they can come into one
of those underground cities

And escape from the other
one and still attack the army.

Narrator: While it appears the
phrygians originally built kaymakli

As a refuge from assailants, it
didn't seem to have been done

With a significant amount of planning.

In later centuries,

Residents found new uses
for these underground spaces.

Asli ozbay's insight sheds some light

On what happened in kaymakli

Since the phrygians
occupied the underground city.

Historians have found evidence
of continues use of kaymakli

By many civilizations up to the present.

Over the millennia, different cultures

Have used this incredible space,

Yet what's remarkable is
that this underground marvel

Was ever created in the first place.

Oh, yeah. That's true.

And the different societies
that made use of this labyrinth

Left behind clues of
how they used this space.

The rock walls offer insights
as to the ingenious techniques

They would have used for food preservation.

Ozbay: They stick branches into holes,

And they used to hang their fruits

And vegetables onto the branches,

So that's how they dried them out.

Narrator: The kitchen
area includes other tools,

Such as a stone grain mill.

They put a small wooden handle here,

Gradually turning it
and grinding the grains,

Obtaining flour to make
their breads or whatever else.

Narrator: Other signs
suggest the inhabitants

Literally brought everything
into these caves with them.

Ozbay: When you see
an animal-tie hole here,

It shouldn't be at the same spot,

Where they dry their
fruits and tie their animals,

So you understand that
probably, before, it was a storage,

Then, in time, it became a barn kind of.

Narrator: By the 4th century ad,

The cappadocia region was
part of the byzantine empire,

A powerful cultural and military force,

Rooted in orthodox christianity.

This room is known as the church.

Narrator: The local
bishop, st. Basil the great,

Founded numerous places
of worship in the region,

Including one within
this subterranean space.

Monastic orders started here by the guy

Called basilius the great
around 4th century ad.

They were trying to imitate
a normal church construction.

There is one small niche here.

Right, you can see it's also blackened.

They would put a small
terra-cotta or lamp in here.

Another one is right there.

Narrator: The last christians
left both these caves

And the country entirely in 1923,

When the modern state
of turkey was founded.

Abandoned for 40 years,
the caves were finally restored

And opened to the public in 1964.

It took us quite a long time in those days

Trying to figure out what is what.

Now, they've got nice signs.

Narrator: But the old cappadocian
traditions of underground

Dwelling are enjoying a resurgence

Thanks to the work of architects like asli,

Who is turning old caves into remarkable

New living spaces for homes and hotels.

This is modern cappadocia.

One has been turned into a bathroom space.

You can still see the original niches

With the fireplace in the middle.

Here we are in the old stable room,

And today we are using it
as a nice wardrobe room.

Narrator: The underground city of
kaymakli remains an enigma for historians

Who continue to look for clues

About what happened here in centuries past,

Yet this subterranean haven is
a testament to human ingenuity.



The czech republic, a
country in central europe

Formed where the ancient
kingdom of bohemia once reigned.

Today, it boasts a population
of just over 10 million

With pilsen as its fourth-largest city.

Nearly 55 miles west
of the capital, prague,

There's a rich history of beer brewing here

Dating back to the 14th century,

A tradition which has given rise

To an extraordinary network of cellars,

Wells and tunnels,
which lie under this city.

How did they harness the power
of nature to create liquid gold?

And how did these secret passages

Give birth to the most popular
fermented beverage ever?





Narrator: Pilsen is an
ancient city founded in 1295

By bohemian king wencelaus
ii on an important trade route

Where four rivers meet.

During a time when fresh
water was unsafe to drink,

The locals turned to
fermented beverages to survive,

And handcrafted
tunnels aided in that effort,

So what led residents
to excavate these tunnels

And vaulted chambers in the first place?

Local historian jan hus first
came here with his father

When he just 14, and ever since,

He's been fascinated by
this underground labyrinth.

Beneath the historic city of pilsen

Lies a subterranean network of cellars,

Wells and storerooms,

Linked together by a complex chain

Of interconnecting tunnels.

As he makes his way into this labyrinth,

Jan is traveling back through time

To the beginning of the pilsen story,

One that would impact
the course of history.

Local monks first brewed
beer here in the 1300s.

The water quality was ideal
because of it's low alkalinity.

Townspeople caught on and
began to make their own beer

By creating wells to
access the water supply.

During the middle ages,
europe was rife with plague

And waterborne disease,

Which meant it was safer to
drink beer rather than water

Because the fermentation
process kills unwanted bacteria.

So how did residents construct
these underground tunnels,

And how would they go on to
change the future of brewing?

You can literally touch the history.

Narrator: Having perfected
their digging methods,

The 14th-century residents of pilsen

Carved out cellars for storage and brewing.

To this day, you can find these relics.

Many homes in the city have ancient cellars

Running three-stories deep.

Little did they know
their efforts would go on

To change the course of beer making.



The oldest corridors
here are only 5-feet tall.

Today, an adult of average
height would struggle

To fit through them.

The labyrinth grew organically
as individual householders

Carved out their basements
to suit their own needs.

The residents were known
to use this cave system

Beyond everyday purposes.

In times of war, they turned to
the tunnels to save their lives.

During medieval times,

The kingdom of bohemia was often at war.

When pilsen's residents
found themselves under siege,

They were able to evade their enemies

And use the tunnels to spring
stealth attacks on invaders.



So how did the residents centuries ago

Make the rudimentary cave system

That would one day become world-famous?

Sandstone is a porous, sedimentary rock,

Which can be unstable.

As the underground labyrinth expanded

And the width of the corridors increased,

It became necessary to support them

To stop them from caving in.

The residents made full
use of the labyrinth's cool,

Ambient temperature.

This was integral to the development

Of the brewing industry,

For which pilsen was
to become world-famous.

The history of pilsen
and its brewing tradition

Are intimately entwined with
the city's subterranean character.

By the 19th century, a major
revolution was on its way.

Pilsen cottage industry
of brewing in private cellars

Was about to become a worldwide phenomenon.



Narrator: Pilsen in the czech
republic has a brewing tradition

Dating back to the 14th century,

Entwined with its underground
network of cellars and tunnels.

Beer quality varied from
one small brewery to another,

So the city elders founded
a large-scale brewery

To standardize their product.

The collective brewery opened in 1839.

Here, a unique form of beer was developed,

Which was to become one of the
world's most popular beverages.

Vaclav berka has held a key
role in the brewery since 1982.

He's the brewmaster,
like his father before him.

Vaclav is preserving a
tradition that connects back

To the original invention of
the now world-famous local beer.

Joseph groll was the
first brewmaster in pilsen.

He came from bavaria,
which is now part of germany.

Groll was experimenting with lager,

A new beer-making process
spreading across europe

In the mid 19th century.

By adapting the technique
to suit the local soft water,

Groll ended up creating
the first golden lager,

Which is called pilsner, after the town.

Malt, barley and hops
are combined with water

To make lager.

The name comes from the
german word for storehouse

Because the beer matured
slowly and at very low temperatures

And in caves or cellars.

So in the 1840s, when the people
of pilsen decided to brew lager

On an industrial scale,

They needed enormous cooling
cellars to ferment their beer.

A city that already had
one massive labyrinth

Was about to dig itself another one.

Historian jan has come to
the most remarkable feature

Of the pilsen cellars,

The staggering rooms
that were built to create

A rudimentary refrigeration system.

The innovation in these enormous cellars

Was that the ice would
slowly melt and trickle

Into a series of channels
running along the floor

To cool every room throughout the brewery.

The scale and innovation

Continued in these giant cellars,

Where fermentation and maturation

Originally took place.

Each cellar is 23-feet
wide and 30-feet deep.

This underground marvel

Is an ingenious 19th-century masterpiece,

Much copies, but rarely better.

Pilsen's world-renowned
drink owes its popularity

To a fine tradition of
underground excavation.

It's remarkable to think
that a system of wells, cellars

And tunnels dating back to the 13th century

Led to the creation of a
brewery in the 19th century,

Which in turn relied on a
brilliant new system of tunnels

And ice-water channels
to produce its famous lager,

Now a global success story.