Underground Marvels (2019–…): Season 1, Episode 2 - Sweden - full transcript
Explores how Sweden has gone to extraordinary lengths to protect itself - by excavating 65,000 nuclear bunkers. Plus, Somerset's Cheddar Gorge and an underground first in Romania.
Narrator: Found deep
within limestone bedrock,
A prehistoric relic changes our
understanding of early humans.
Targett: What I really wasn't
prepared for was the extent
To which this story suddenly became global.
Narrator: Beneath a capital city,
Giant cold war atomic bunkers.
How has one of them been transformed?
Hidden beneath the surface,
Inside a nearly mile-thick
layer of salt, is a world first.
Beneath our feet lie
extraordinary chambers,
Caves, vaults, and tunnels...
The span and the size is just crazy.
...Some designed and built by humans,
Others formed over thousands of years.
But how were they created and adapted?
By who, and why?
You've got to face your fears.
Throughout history, subterranean life
Has captured our imagination.
We're going further and deeper
To unearth their mysteries, Stories,
And secrets.
Hidden underneath a peaceful landscape
Lie chilling reminders of a sinister past.
Everyone knew that the war could come.
Narrator: These haunting
relics prove that destruction
Could be right around the corner.
Olgarsson: It's made to
protect people from the blasts,
From the radiation, and from poison gases.
Narrator: But how were these
impenetrable subterranean spaces created?
This place could house up to 16,000 people.
Narrator: Why were
they critical to survival?
Olgarsson: The ground and the walls shake.
Narrator: And how are they being
reinvented to provide protection
For our modern world?
♪
From the mid 1940s to
the early 1990s, sweden,
Precariously located
between russia and the west,
Needed to protect itself
against nuclear attack.
Olgarsson: The strategic
position of sweden,
We had to defend our territory
And defend the civil structures of society.
Many countries in europe,
among them sweden,
Started to shield the population
So that people could survive an attack.
This symbol, orange
square and a blue triangle,
Tells you that this is a public shelter.
Narrator: Hidden underground
are giant cold war nuclear bunkers
Built into the very
bedrock below stockholm.
♪
Deep beneath the capital city
Is a vast space called klara shelter.
And how the swedish engineers
designed this cavernous shelter
Is unexpected and revolutionary.
To this day, the ability of the spaces
To protect what's
important to us is unrivaled.
Olgarsson: We are standing
in the main shelter tunnel,
And this is actually a house within a cave,
And the point is that you
have the ability for the rock
And the building to move separately.
So if there's an atomic
bomb blast above our heads,
The rock will shake,
But the building will not shake with it.
Narrator: Klara shelter was
built between 1958 and 1961.
It can be turned into an
emergency population shelter
In less than 48 hours.
It's one of four large population shelters,
And this place could
house up to 16,000 people.
Narrator: But how was this
underground layer made possible
Below a major city,
A space that continues to protect
Sweden's most important assets?
Olgarsson: To make klara shelter,
They had to blast 65,000
cubic meters of bedrock.
To build the shelter itself,
They needed 12,000 cubic
meters of reinforced concrete.
Narrator: Hidden 50 feet below the surface,
These subterranean shelters are accessible
From designated access points aboveground.
Olgarsson: If the air-raid sirens went off,
People would rush down the
many stairways from streets,
From the subway, and then
come into the large tunnels,
And then the blast doors would close.
♪
One can only imagine
20,000 people down here,
And this light starts to flicker,
And the ground and the walls shake.
It would have been quite terrifying.
Narrator: In an attempt to
diminish the potential chaos,
The designers of these hidden
spaces tried to create order.
Olgarsson: The color-coding
on the railing here
Is to show different kinds
of people the right way down.
You have to imagine hundreds,
Even thousands of people
rushing down these stairways.
You're a pregnant woman?
Yellow railing.
Healthy, green.
City official, red.
Narrator: Doors made of steel
and concrete, weighing 70 tons,
Were built to withstand a nuclear blast
Nearly a mile away,
A design feature that was just
as important during the cold war
As it is today.
Olgarsson: This is the main
blast doors for the shelter,
And in case of an emergency,
they would shut automatically,
And they are powered
by small diesel engines,
And when they are closed,
The plates on the ground flips up,
And that is how you seal the place off
Because the blast from a nuclear explosion,
The pressure, the air
pressure, rises very, very quickly,
So the doors would have to handle that.
These specific doors, they
can close in 2 or 3 minutes.
It's made to protect
people from the blasts,
From the radiation, and from
poison gases, fire, and so on.
Narrator: In the event of a nuclear attack,
Sweden's citizens had to
prepare to survive down here
For up to a month while awaiting rescue.
People were supposed
to bring with them blankets
And some food, canned
foods, bread and so on.
Everything down here is
supposed to be functioning
Even after the municipal
power has been shut down...
Wells, water cisterns,
air-purification facilities,
Reserve power plants.
This place is supposed
to be totally self-sufficient.
Narrator: Yet the survivors
couldn't stay underground forever
And would eventually have
to brave their new reality.
Olgarsson: You would have to
send someone up to the surface
To check for radiation.
So that person would
then dress in a hazard suit
And venture out with a geiger counter
And measure how danger it is,
and then when they come down,
They will not be allowed
into this sealed space.
They would have to speak
via these kind of systems
To the guards inside,
And these are for when
it's okay to come inside
And when it's not okay to come inside.
And if everything is okay,
the inner doors are opened.
So there was a system for
gaining entrance to this place
Once the large blast doors were closed.
Narrator: Fortunately,
these underground bunkers
Never had to fulfill their stated purpose.
They remain intact and at the ready
Should the country ever come under threat.
They now sit empty as a monument to a war
That all are grateful never happened,
And now other nearby caverns of last resort
Are welcoming locals in a
much more appealing way,
One that their original creators
could never have imagined.
♪
Narrator: During the cold war era,
Sweden took extraordinary precautions
To protect its people from
potential nuclear fallout,
With vast subterranean shelters.
Positioned in between russia and the west,
War was an ever-present threat.
Today, times have changed,
But sweden remains alert to dangers.
[ siren blaring ]
Four times a year, it
tests its public alert system.
In 2018, sweden's government
issued emergency instructions
To its population called
"if crisis or war comes."
It was sent to 4.8 million households.
While the country remains prepared,
New life is being breathed
into other former bunkers
Which continue to serve the people,
Although their transformation
got off to a rocky start.
[ siren blares ]
In 2007, underground explosions
Shuddered through central stockholm.
1.4 million cubic feet of solid rock
Was being removed to tap into
And extend a vast underground network
That was originally dug out in the 1940s.
Jon karlung was excavating
a unique workplace
For his company.
Jon's business stores
And protects sweden's digital information
In what are known as data centers.
He's found an underground location
Where security was already built in...
A subterranean space
That used to be a cold war nuclear bunker.
Historian per olgarsson is meeting jon
At the pionen facility 2 miles
away from the klara shelter
To explore his vision of future security.
This is amazing. Why
do you have blast doors?
What do you need them for?
It's a matter of security.
This is an ultra-high-security facility,
So this is the reason that we use them.
I like that you kept raw rock walls.
It also shows you a bit of
how this place used to be
When it was used as a shelter.
Actually, we have an alarm, as well.
We have a second world war
German sub alarm, as well. Yeah?
Alarm! Alarm! [ laughs ]
Then this sounds.
[ alarm blares ]
Olgarsson: Sweden was preparing itself
For a war that never came.
If people want to learn
About the second half Of the 20th century,
They just have to open a
door to one of these shelters.
Narrator: What did it
take to convert this relic
Of the nuclear arms race?
Architect albert France-lanord was tasked
With making jon's vision a reality.
♪
The data center now boasts waterfalls,
A vertical garden, low-lying fog,
And a climate-controlled
suspended glass conference room.
♪
Visitors to the pionen
facility are often struck
By its resemblance to the villain's lair
In an old james bond film.
This reimagined subterranean structure
Still plays an important
role in protecting sweden.
The facility is designed so
that the power supply never fails.
Two giant backup engines
stand ready to produce
1.5 megawatts of power
in the event of a crisis.
...That take over if the grid fails...
Olgarsson: These places
are part of our history
Because they can explain to us
In a very evocative way
The world of the cold war,
What it was like to live
during the cold war era,
And know that the nuclear
war can come tomorrow.
Narrator: And by embracing its past,
Sweden is boldly
leading us into the future.
Deep within southwest England
lies a spectacular landscape
That took tens of thousands of years
To etch out of the earth...
...Cheddar gorge.
Formed more than 1 million years ago
When melting glacial waters
Carved through the limestone rock...
...It left behind near vertical cliffs
And a mysterious subterranean world.
♪
Beneath this landscape lies secret caverns
And breathtaking rock formations,
But these caverns also contain
A history-making 10,000-year-old find
That sent shock waves
through the scientific community.
Hemington: Can you imagine
seeing this for the first time?
You'd be like, "wow! What's this?!"
Why did humans come here to explore?
What can we learn from its hidden secrets?
And what discovery was made that changed
Our entire understanding of the people
Who have lived here for millennia?
Targett: What I really wasn't
prepared for was the extent
To which this story suddenly became global.
♪
Narrator: Carved by melting glacial waters
Over a million years ago,
This gorge in southwest England
Is almost 400 feet deep And 3 miles long.
The famous cheese gets its
name from this unique region,
But it's also a home to
a lesser-known wonder.
♪
At its heart is one of britain's
oldest underground marvels,
Cheddar caves.
♪
Known to humans for thousands of years,
This cave system hides both man-made
And natural marvels deep inside.
The story of this magnificent cave system
Begins at its entrance,
Where an extraordinary
discovery was made in 1903...
The oldest complete prehistoric skeleton
Ever found in britain,
nearly 10,000 years old.
Ancient remains from the mouth of the cave
Told scientists that generations of humans
Had lived here for millennia,
But little more was known
about their way of life.
So in 1997, a team from oxford university
Conducted a dna test
to find any living relatives
Of the so-called cheddar
man among local residents.
History teacher adrian targett
was among the volunteers.
What I really wasn't
prepared for was the extent
To which this story suddenly became global.
In the test, mitochondrial
dna was extracted
From one of cheddar man's molars
And compared to samples from 20 volunteers,
All known to have
families living in the area
For many generations.
We were told, "there was only one result,
And it's you.
You're the one."
So it was a bit of a shock.
Narrator: But it would be 20 years
Before he'd get to see the
family resemblance for himself.
Paul hemington is an expert on these caves.
He's meeting cheddar man's
direct descendant, adrian,
In the exact place near the cave entrance
Where the skeleton was
originally found in 1903.
So that would have been
quite a good diet, actually,
Wouldn't it?
Cheddar man was discovered in 1903
During the reign of queen victoria,
When a new wave of
tourism was taking place.
The middle classes had the
luxury of more time and money
Than previous generations,
and although cheddar caves
Were mainly a local attraction at the time,
Their popularity was about to skyrocket.
Yet ancient cheddar man
and this subterranean labyrinth
Might have been lost to history
If it were not for local man richard gough.
He saw an opportunity to take advantage
Of the unprecedented number
of tourists flocking to cheddar
By opening these caves to the public.
The caves were known
long before gough's time,
But it hadn't been possible
to explore their full extent
Before he and his two sons
dug it all out in the 1890s.
For 2 years, richard and his sons
Continued this painstaking work,
On their hands and knees, into the unknown.
His first discovery was breathtaking.
He called them the fonts.
Hemington: He named the fonts
After what you would see within a church,
The fonts that were used
to baptize babies with.
That's what they reminded him of.
Can you imagine seeing
this for the first time?
You'd be like, "wow, what's this?"
Formed over thousands of years,
Pure white crystals
called calcite are deposited
When rainwater with
dissolved limestone evaporates.
It takes about 1,000 years
for a cubic centimeter to form.
Calcite is white in its purest form,
And the red is iron oxide,
which is all mixed together
To give that wonderful
sort of dry waterfall effect.
This is the power of nature.
This is what nature can do.
This is what water can do.
It makes you feel quite small, in a way,
To see the wonderments
of how this has been formed.
When gough and his sons
Were excavating these caves in the 1890s,
They had no idea that
human skeletal remains
Thousands of years old lay nearby
And would have such a huge impact
On our understanding
of the history of humanity.
Their work would one day
bring modern man face-to-face
With a 10,000-year-old relative.
Narrator: During the late
1800s in southwest England,
Entrepreneur richard
gough excavated tons of rock
To create the subterranean
tourist attraction
Known as the cheddar caves.
He was looking for a money-making venture,
But what he found would change the thinking
About the prehistoric people
Who called these caves their home.
Today, adrian targett,
A descendant of the famous
prehistoric cheddar man,
And paul hemington,
an expert on these caves,
Are exploring these sites.
These spaces continue to teach us
About the prehistory of this area.
♪
While they could have no idea
of the human remains awaiting,
Gough found further success
In making the caves
a spectacle for tourists
When he broke through
to the diamond chamber.
By 1899, the subterranean world
Once lit by candles and gas lamps
Could now be brilliantly
displayed in electric light.
Okay, adrian. Check this out.
♪
Wow. Look at that.
That's amazing, isn't it?
The diamond chamber is 100 feet high
And is thought to contain
around 60,000 tons
Of stunningly sculpted limestone.
It's the last and largest of
gough's discoveries and home
To an eye-catching formation
known as niagara falls,
Formed when stalactites
and stalagmites join together.
♪
It's believed that the cave
dried out 250,000 years ago.
Hemington: It's like a journey,
A journey through time... Yes.
...And nature itself,
And that's really what
makes this so, so special.
For richard gough to reach this point,
It took him 8 years of his life,
And he was 71 by the time
he reached this end chamber.
10,000 years after
cheddar man lived and died
At the mouth of this
cave, his ancestor, adrian,
Has now walked into the past
To take in the underground marvels
That were just out of reach
for prehistoric humans.
Targett: It's amazing to
think that cheddar man,
Who resided at the entrance to the cave,
Never realized that he
was on the threshold,
If you like, of a fabulous
underground world.
♪
To this day, explorers
continue to search these caves
Just like gough did.
As recently as 2010, human
bones have been found
And examined from cheddar caves.
Ultrafiltration carbon dating has revealed
They're from the end of the ice age,
A staggering 14,700 years ago.
One of the experts who
continues to explore cheddar caves
Is sam rasmussen.
Rasmussen: It's not
really for the faint-hearted.
You've got to kind of face your fears
As you go through the cave.
Narrator: To see just how challenging
Gough would have found
Navigating the cheddar cave systems,
Sam films himself on a small camera.
Over 100 years later,
It's still a life-threatening adventure.
Rasmussen: Uncharted
caves can be very, very tight.
They can have loose
rocks as you go through.
So, of course, you do
have the risk of rock falls
Perhaps happening.
There are certain
passages you could go down,
And they suddenly
drop out, say, 40, 50 feet.
So you need to be prepared
for these things to happen,
But, of course, we can only be so prepared.
Going further in, of course,
there will be no natural light.
Wave your hand in front of your face,
You won't be able to see it at all.
You can open and close your eyes.
It'll be exactly the same.
You won't see any difference at all.
Narrator: Hidden from view,
The further wonders
of the cave are reserved
For only the bravest visitors.
Crawling through these narrow spaces
Can be both claustrophobic and dangerous.
You see small gaps that
you perhaps want to give a go
At trying to get through.
Narrator: The more scientists
explore the cheddar caves,
The more discoveries they make.
Human bones have shown
cut marks and breakage
Consistent with defleshing and eating.
Some experts believe this
is evidence of cannibalism.
Gough and his sons were unimaginably brave
To excavate these caves
And bring them to the
attention of the world,
But it was the cheddar man
Who would bring the most
attention to his former home,
Especially when he finally showed his face.
Merely 20-something years
old and lactose-intolerant,
This hunter-gatherer was long assumed
To have been pale-skinned,
With blond hair and light-colored eyes,
Like the locals are known for today,
But revolutionary facial
reconstruction proved otherwise,
And in 2018, further dna research
And high-tech scans unveiled a cheddar man
That was, in fact, dark-skinned,
With dark hair and bluish-green eyes.
These genetic findings have
changed our understanding
Of human evolution and migration
And cemented the notoriety of gough's caves
In the history books.
♪
The historic region of
transylvania lies at the center
Of romania, bordering the black sea.
This is a country better
known for its brutal ruler,
Vlad the impaler, and the dracula legend...
♪
...Than for the centuries
it served as a hub
For natural resources.
Yet this landmass,
Surrounded by the great
carpathian mountain range,
Hides one of history's great
underground spectacles.
Popa: This location is
actually one of our secrets.
Narrator: How were these
huge caverns created?
And what modern-day transformations make it
A one-of-a-kind subterranean space?
♪
Narrator: 13 million years
ago in what is now romania,
A prehistoric sea encircled by mountains
Evaporated over millennia,
Leaving huge salt deposits
covering nearly 17 square miles.
Long before this region
Was associated with the legend of dracula,
It was well-known for what lies beneath it.
Historian paul-florin chiorean
Has been studying the
excavations of salt here
That date back to the
time when rome ruled dacia,
Now modern romania.
Although salt had been mined in this region
Prior to the romans, it
was under their occupation
That it became a lucrative business
And would begin to change
these subterranean spaces
In ways that the miners themselves
Never could have expected.
Salt was prized around
the world for its ability
To preserve and season food.
As the centuries passed,
excavation methods were refined.
Mining expert edmond-cristian popa
Explains the techniques
used by medieval pioneers
To extract salt.
With simple tools,
workers excavated the salt
By digging deeper and deeper,
But the further down they
dug, the more difficult it became
To lift the heavy salt out of the mine.
An ingenious machine was
devised in the 19th century
To make extraction more efficient.
Up to 1,000 pounds of salt
Could be taken out of the mine in one lift.
In addition to this
machine, in the 19th century,
A transportation revolution was introduced
To this subterranean world.
The technique of creating
deep bell-shaped mines
Below a central winch was
used at several locations
In transylvania over the centuries.
The steep-sided walls of these mines
Reduced the risk of collapse,
As workers excavated deeper and deeper.
Paul-florin has joined edmond
to see the deepest mine
And one of the relatively newest ones
Of the salina turda complex
of chambers, the terezia mine.
Industrial mining began here in 1690,
And it took almost 200 years
To create this huge hollow shape.
All the miners' hard
work would set the stage
For a modern-day transformation
that no one could have expected.
The base of the mine is
370 feet below the surface
And 250 feet across.
Due to the gradual infiltration of water
Through the porous salt walls,
A 25-foot deep underground lake has formed.
Blocks of salt that failed
to reach mining standards
Were thrown back into the terezia mine.
Over the years, it's formed
this impressive island
That now stands 16 feet above the water,
And what the island has
been turned into today
Would shock the original miners
Who worked tirelessly
under harsh conditions.
As the mines grew deeper
and deeper over the centuries,
The walls became so heavy
They couldn't hold themselves up.
Reinforcements became necessary.
900 years ago, workers in this mine
Began using spruce wood in all their beams,
Supports, and equipment.
They discovered its loose-grained
structure absorbed salt,
Creating a layer that prevents
the wood from decomposing,
And in present times,
They're still finding innovative
subterranean uses for it.
For centuries, workers continued
to dig deep bell-shaped mines.
However, excavating large
amounts of salt from the bottom
Was time-consuming and inefficient.
So after 800 years of
digging down in this way,
Miners realized in the 19th century
That by digging horizontally,
The salt could be more
easily and quickly extracted.
A new way to mine salt was invented.
Salina turda salt mines
have been at the heart
Of this region for centuries,
But in 1932, salt excavation ended here.
To this day, engineers
continue to ensure this incredible
Underground space remains relevant,
And in 2008, a radical
transformation took place
The likes of which the
world had never seen.
Narrator: In historic romania,
Home of transylvania
and the dracula legend,
Salt has been mined from salina turda
For more than 900 years.
Up until 1932, workers
excavated the commodity
From a 1-mile-thick layer of salt.
♪
There are still secret places
to which few have access.
From the highest point
above terezia mine...
...To the deepest, darkest
depths of the neighboring
And abandoned bell-shaped josef chamber,
Where the remnants of the
mining work can still be found,
Something no tourist will witness.
[ echoing voices ]
[ echoing ] hello!
Yet in 2008, one of these giant spaces
Was transformed for the future.
In an unprecedented move,
The world's first underground
amusement park was created.
Within this cavernous realm,
mini golf, bowling, handball
And soccer, badminton, billiards,
And table tennis offer a unique experience
To which no other amusement
park in the world can compare.
♪
There's also a 180-seat amphitheater
For conferences and concerts...
...Plus the most spectacular
attraction, a ferris wheel.
Standing at an impressive 65 feet high,
The ride is the world's first
underground ferris wheel
And offers a unique vantage point
For mining experts edmond and paul-florin.
Popa: The size of the chambers
Was the thing that really surprised me.
So you have no idea when you're above
That, underneath your feet,
You have an underground
world like this one.
♪
The ambition of romania's new underground
Entrepreneurs means
salina turda's past and present
Have been seamlessly combined
For the benefit of generations to come.
within limestone bedrock,
A prehistoric relic changes our
understanding of early humans.
Targett: What I really wasn't
prepared for was the extent
To which this story suddenly became global.
Narrator: Beneath a capital city,
Giant cold war atomic bunkers.
How has one of them been transformed?
Hidden beneath the surface,
Inside a nearly mile-thick
layer of salt, is a world first.
Beneath our feet lie
extraordinary chambers,
Caves, vaults, and tunnels...
The span and the size is just crazy.
...Some designed and built by humans,
Others formed over thousands of years.
But how were they created and adapted?
By who, and why?
You've got to face your fears.
Throughout history, subterranean life
Has captured our imagination.
We're going further and deeper
To unearth their mysteries, Stories,
And secrets.
Hidden underneath a peaceful landscape
Lie chilling reminders of a sinister past.
Everyone knew that the war could come.
Narrator: These haunting
relics prove that destruction
Could be right around the corner.
Olgarsson: It's made to
protect people from the blasts,
From the radiation, and from poison gases.
Narrator: But how were these
impenetrable subterranean spaces created?
This place could house up to 16,000 people.
Narrator: Why were
they critical to survival?
Olgarsson: The ground and the walls shake.
Narrator: And how are they being
reinvented to provide protection
For our modern world?
♪
From the mid 1940s to
the early 1990s, sweden,
Precariously located
between russia and the west,
Needed to protect itself
against nuclear attack.
Olgarsson: The strategic
position of sweden,
We had to defend our territory
And defend the civil structures of society.
Many countries in europe,
among them sweden,
Started to shield the population
So that people could survive an attack.
This symbol, orange
square and a blue triangle,
Tells you that this is a public shelter.
Narrator: Hidden underground
are giant cold war nuclear bunkers
Built into the very
bedrock below stockholm.
♪
Deep beneath the capital city
Is a vast space called klara shelter.
And how the swedish engineers
designed this cavernous shelter
Is unexpected and revolutionary.
To this day, the ability of the spaces
To protect what's
important to us is unrivaled.
Olgarsson: We are standing
in the main shelter tunnel,
And this is actually a house within a cave,
And the point is that you
have the ability for the rock
And the building to move separately.
So if there's an atomic
bomb blast above our heads,
The rock will shake,
But the building will not shake with it.
Narrator: Klara shelter was
built between 1958 and 1961.
It can be turned into an
emergency population shelter
In less than 48 hours.
It's one of four large population shelters,
And this place could
house up to 16,000 people.
Narrator: But how was this
underground layer made possible
Below a major city,
A space that continues to protect
Sweden's most important assets?
Olgarsson: To make klara shelter,
They had to blast 65,000
cubic meters of bedrock.
To build the shelter itself,
They needed 12,000 cubic
meters of reinforced concrete.
Narrator: Hidden 50 feet below the surface,
These subterranean shelters are accessible
From designated access points aboveground.
Olgarsson: If the air-raid sirens went off,
People would rush down the
many stairways from streets,
From the subway, and then
come into the large tunnels,
And then the blast doors would close.
♪
One can only imagine
20,000 people down here,
And this light starts to flicker,
And the ground and the walls shake.
It would have been quite terrifying.
Narrator: In an attempt to
diminish the potential chaos,
The designers of these hidden
spaces tried to create order.
Olgarsson: The color-coding
on the railing here
Is to show different kinds
of people the right way down.
You have to imagine hundreds,
Even thousands of people
rushing down these stairways.
You're a pregnant woman?
Yellow railing.
Healthy, green.
City official, red.
Narrator: Doors made of steel
and concrete, weighing 70 tons,
Were built to withstand a nuclear blast
Nearly a mile away,
A design feature that was just
as important during the cold war
As it is today.
Olgarsson: This is the main
blast doors for the shelter,
And in case of an emergency,
they would shut automatically,
And they are powered
by small diesel engines,
And when they are closed,
The plates on the ground flips up,
And that is how you seal the place off
Because the blast from a nuclear explosion,
The pressure, the air
pressure, rises very, very quickly,
So the doors would have to handle that.
These specific doors, they
can close in 2 or 3 minutes.
It's made to protect
people from the blasts,
From the radiation, and from
poison gases, fire, and so on.
Narrator: In the event of a nuclear attack,
Sweden's citizens had to
prepare to survive down here
For up to a month while awaiting rescue.
People were supposed
to bring with them blankets
And some food, canned
foods, bread and so on.
Everything down here is
supposed to be functioning
Even after the municipal
power has been shut down...
Wells, water cisterns,
air-purification facilities,
Reserve power plants.
This place is supposed
to be totally self-sufficient.
Narrator: Yet the survivors
couldn't stay underground forever
And would eventually have
to brave their new reality.
Olgarsson: You would have to
send someone up to the surface
To check for radiation.
So that person would
then dress in a hazard suit
And venture out with a geiger counter
And measure how danger it is,
and then when they come down,
They will not be allowed
into this sealed space.
They would have to speak
via these kind of systems
To the guards inside,
And these are for when
it's okay to come inside
And when it's not okay to come inside.
And if everything is okay,
the inner doors are opened.
So there was a system for
gaining entrance to this place
Once the large blast doors were closed.
Narrator: Fortunately,
these underground bunkers
Never had to fulfill their stated purpose.
They remain intact and at the ready
Should the country ever come under threat.
They now sit empty as a monument to a war
That all are grateful never happened,
And now other nearby caverns of last resort
Are welcoming locals in a
much more appealing way,
One that their original creators
could never have imagined.
♪
Narrator: During the cold war era,
Sweden took extraordinary precautions
To protect its people from
potential nuclear fallout,
With vast subterranean shelters.
Positioned in between russia and the west,
War was an ever-present threat.
Today, times have changed,
But sweden remains alert to dangers.
[ siren blaring ]
Four times a year, it
tests its public alert system.
In 2018, sweden's government
issued emergency instructions
To its population called
"if crisis or war comes."
It was sent to 4.8 million households.
While the country remains prepared,
New life is being breathed
into other former bunkers
Which continue to serve the people,
Although their transformation
got off to a rocky start.
[ siren blares ]
In 2007, underground explosions
Shuddered through central stockholm.
1.4 million cubic feet of solid rock
Was being removed to tap into
And extend a vast underground network
That was originally dug out in the 1940s.
Jon karlung was excavating
a unique workplace
For his company.
Jon's business stores
And protects sweden's digital information
In what are known as data centers.
He's found an underground location
Where security was already built in...
A subterranean space
That used to be a cold war nuclear bunker.
Historian per olgarsson is meeting jon
At the pionen facility 2 miles
away from the klara shelter
To explore his vision of future security.
This is amazing. Why
do you have blast doors?
What do you need them for?
It's a matter of security.
This is an ultra-high-security facility,
So this is the reason that we use them.
I like that you kept raw rock walls.
It also shows you a bit of
how this place used to be
When it was used as a shelter.
Actually, we have an alarm, as well.
We have a second world war
German sub alarm, as well. Yeah?
Alarm! Alarm! [ laughs ]
Then this sounds.
[ alarm blares ]
Olgarsson: Sweden was preparing itself
For a war that never came.
If people want to learn
About the second half Of the 20th century,
They just have to open a
door to one of these shelters.
Narrator: What did it
take to convert this relic
Of the nuclear arms race?
Architect albert France-lanord was tasked
With making jon's vision a reality.
♪
The data center now boasts waterfalls,
A vertical garden, low-lying fog,
And a climate-controlled
suspended glass conference room.
♪
Visitors to the pionen
facility are often struck
By its resemblance to the villain's lair
In an old james bond film.
This reimagined subterranean structure
Still plays an important
role in protecting sweden.
The facility is designed so
that the power supply never fails.
Two giant backup engines
stand ready to produce
1.5 megawatts of power
in the event of a crisis.
...That take over if the grid fails...
Olgarsson: These places
are part of our history
Because they can explain to us
In a very evocative way
The world of the cold war,
What it was like to live
during the cold war era,
And know that the nuclear
war can come tomorrow.
Narrator: And by embracing its past,
Sweden is boldly
leading us into the future.
Deep within southwest England
lies a spectacular landscape
That took tens of thousands of years
To etch out of the earth...
...Cheddar gorge.
Formed more than 1 million years ago
When melting glacial waters
Carved through the limestone rock...
...It left behind near vertical cliffs
And a mysterious subterranean world.
♪
Beneath this landscape lies secret caverns
And breathtaking rock formations,
But these caverns also contain
A history-making 10,000-year-old find
That sent shock waves
through the scientific community.
Hemington: Can you imagine
seeing this for the first time?
You'd be like, "wow! What's this?!"
Why did humans come here to explore?
What can we learn from its hidden secrets?
And what discovery was made that changed
Our entire understanding of the people
Who have lived here for millennia?
Targett: What I really wasn't
prepared for was the extent
To which this story suddenly became global.
♪
Narrator: Carved by melting glacial waters
Over a million years ago,
This gorge in southwest England
Is almost 400 feet deep And 3 miles long.
The famous cheese gets its
name from this unique region,
But it's also a home to
a lesser-known wonder.
♪
At its heart is one of britain's
oldest underground marvels,
Cheddar caves.
♪
Known to humans for thousands of years,
This cave system hides both man-made
And natural marvels deep inside.
The story of this magnificent cave system
Begins at its entrance,
Where an extraordinary
discovery was made in 1903...
The oldest complete prehistoric skeleton
Ever found in britain,
nearly 10,000 years old.
Ancient remains from the mouth of the cave
Told scientists that generations of humans
Had lived here for millennia,
But little more was known
about their way of life.
So in 1997, a team from oxford university
Conducted a dna test
to find any living relatives
Of the so-called cheddar
man among local residents.
History teacher adrian targett
was among the volunteers.
What I really wasn't
prepared for was the extent
To which this story suddenly became global.
In the test, mitochondrial
dna was extracted
From one of cheddar man's molars
And compared to samples from 20 volunteers,
All known to have
families living in the area
For many generations.
We were told, "there was only one result,
And it's you.
You're the one."
So it was a bit of a shock.
Narrator: But it would be 20 years
Before he'd get to see the
family resemblance for himself.
Paul hemington is an expert on these caves.
He's meeting cheddar man's
direct descendant, adrian,
In the exact place near the cave entrance
Where the skeleton was
originally found in 1903.
So that would have been
quite a good diet, actually,
Wouldn't it?
Cheddar man was discovered in 1903
During the reign of queen victoria,
When a new wave of
tourism was taking place.
The middle classes had the
luxury of more time and money
Than previous generations,
and although cheddar caves
Were mainly a local attraction at the time,
Their popularity was about to skyrocket.
Yet ancient cheddar man
and this subterranean labyrinth
Might have been lost to history
If it were not for local man richard gough.
He saw an opportunity to take advantage
Of the unprecedented number
of tourists flocking to cheddar
By opening these caves to the public.
The caves were known
long before gough's time,
But it hadn't been possible
to explore their full extent
Before he and his two sons
dug it all out in the 1890s.
For 2 years, richard and his sons
Continued this painstaking work,
On their hands and knees, into the unknown.
His first discovery was breathtaking.
He called them the fonts.
Hemington: He named the fonts
After what you would see within a church,
The fonts that were used
to baptize babies with.
That's what they reminded him of.
Can you imagine seeing
this for the first time?
You'd be like, "wow, what's this?"
Formed over thousands of years,
Pure white crystals
called calcite are deposited
When rainwater with
dissolved limestone evaporates.
It takes about 1,000 years
for a cubic centimeter to form.
Calcite is white in its purest form,
And the red is iron oxide,
which is all mixed together
To give that wonderful
sort of dry waterfall effect.
This is the power of nature.
This is what nature can do.
This is what water can do.
It makes you feel quite small, in a way,
To see the wonderments
of how this has been formed.
When gough and his sons
Were excavating these caves in the 1890s,
They had no idea that
human skeletal remains
Thousands of years old lay nearby
And would have such a huge impact
On our understanding
of the history of humanity.
Their work would one day
bring modern man face-to-face
With a 10,000-year-old relative.
Narrator: During the late
1800s in southwest England,
Entrepreneur richard
gough excavated tons of rock
To create the subterranean
tourist attraction
Known as the cheddar caves.
He was looking for a money-making venture,
But what he found would change the thinking
About the prehistoric people
Who called these caves their home.
Today, adrian targett,
A descendant of the famous
prehistoric cheddar man,
And paul hemington,
an expert on these caves,
Are exploring these sites.
These spaces continue to teach us
About the prehistory of this area.
♪
While they could have no idea
of the human remains awaiting,
Gough found further success
In making the caves
a spectacle for tourists
When he broke through
to the diamond chamber.
By 1899, the subterranean world
Once lit by candles and gas lamps
Could now be brilliantly
displayed in electric light.
Okay, adrian. Check this out.
♪
Wow. Look at that.
That's amazing, isn't it?
The diamond chamber is 100 feet high
And is thought to contain
around 60,000 tons
Of stunningly sculpted limestone.
It's the last and largest of
gough's discoveries and home
To an eye-catching formation
known as niagara falls,
Formed when stalactites
and stalagmites join together.
♪
It's believed that the cave
dried out 250,000 years ago.
Hemington: It's like a journey,
A journey through time... Yes.
...And nature itself,
And that's really what
makes this so, so special.
For richard gough to reach this point,
It took him 8 years of his life,
And he was 71 by the time
he reached this end chamber.
10,000 years after
cheddar man lived and died
At the mouth of this
cave, his ancestor, adrian,
Has now walked into the past
To take in the underground marvels
That were just out of reach
for prehistoric humans.
Targett: It's amazing to
think that cheddar man,
Who resided at the entrance to the cave,
Never realized that he
was on the threshold,
If you like, of a fabulous
underground world.
♪
To this day, explorers
continue to search these caves
Just like gough did.
As recently as 2010, human
bones have been found
And examined from cheddar caves.
Ultrafiltration carbon dating has revealed
They're from the end of the ice age,
A staggering 14,700 years ago.
One of the experts who
continues to explore cheddar caves
Is sam rasmussen.
Rasmussen: It's not
really for the faint-hearted.
You've got to kind of face your fears
As you go through the cave.
Narrator: To see just how challenging
Gough would have found
Navigating the cheddar cave systems,
Sam films himself on a small camera.
Over 100 years later,
It's still a life-threatening adventure.
Rasmussen: Uncharted
caves can be very, very tight.
They can have loose
rocks as you go through.
So, of course, you do
have the risk of rock falls
Perhaps happening.
There are certain
passages you could go down,
And they suddenly
drop out, say, 40, 50 feet.
So you need to be prepared
for these things to happen,
But, of course, we can only be so prepared.
Going further in, of course,
there will be no natural light.
Wave your hand in front of your face,
You won't be able to see it at all.
You can open and close your eyes.
It'll be exactly the same.
You won't see any difference at all.
Narrator: Hidden from view,
The further wonders
of the cave are reserved
For only the bravest visitors.
Crawling through these narrow spaces
Can be both claustrophobic and dangerous.
You see small gaps that
you perhaps want to give a go
At trying to get through.
Narrator: The more scientists
explore the cheddar caves,
The more discoveries they make.
Human bones have shown
cut marks and breakage
Consistent with defleshing and eating.
Some experts believe this
is evidence of cannibalism.
Gough and his sons were unimaginably brave
To excavate these caves
And bring them to the
attention of the world,
But it was the cheddar man
Who would bring the most
attention to his former home,
Especially when he finally showed his face.
Merely 20-something years
old and lactose-intolerant,
This hunter-gatherer was long assumed
To have been pale-skinned,
With blond hair and light-colored eyes,
Like the locals are known for today,
But revolutionary facial
reconstruction proved otherwise,
And in 2018, further dna research
And high-tech scans unveiled a cheddar man
That was, in fact, dark-skinned,
With dark hair and bluish-green eyes.
These genetic findings have
changed our understanding
Of human evolution and migration
And cemented the notoriety of gough's caves
In the history books.
♪
The historic region of
transylvania lies at the center
Of romania, bordering the black sea.
This is a country better
known for its brutal ruler,
Vlad the impaler, and the dracula legend...
♪
...Than for the centuries
it served as a hub
For natural resources.
Yet this landmass,
Surrounded by the great
carpathian mountain range,
Hides one of history's great
underground spectacles.
Popa: This location is
actually one of our secrets.
Narrator: How were these
huge caverns created?
And what modern-day transformations make it
A one-of-a-kind subterranean space?
♪
Narrator: 13 million years
ago in what is now romania,
A prehistoric sea encircled by mountains
Evaporated over millennia,
Leaving huge salt deposits
covering nearly 17 square miles.
Long before this region
Was associated with the legend of dracula,
It was well-known for what lies beneath it.
Historian paul-florin chiorean
Has been studying the
excavations of salt here
That date back to the
time when rome ruled dacia,
Now modern romania.
Although salt had been mined in this region
Prior to the romans, it
was under their occupation
That it became a lucrative business
And would begin to change
these subterranean spaces
In ways that the miners themselves
Never could have expected.
Salt was prized around
the world for its ability
To preserve and season food.
As the centuries passed,
excavation methods were refined.
Mining expert edmond-cristian popa
Explains the techniques
used by medieval pioneers
To extract salt.
With simple tools,
workers excavated the salt
By digging deeper and deeper,
But the further down they
dug, the more difficult it became
To lift the heavy salt out of the mine.
An ingenious machine was
devised in the 19th century
To make extraction more efficient.
Up to 1,000 pounds of salt
Could be taken out of the mine in one lift.
In addition to this
machine, in the 19th century,
A transportation revolution was introduced
To this subterranean world.
The technique of creating
deep bell-shaped mines
Below a central winch was
used at several locations
In transylvania over the centuries.
The steep-sided walls of these mines
Reduced the risk of collapse,
As workers excavated deeper and deeper.
Paul-florin has joined edmond
to see the deepest mine
And one of the relatively newest ones
Of the salina turda complex
of chambers, the terezia mine.
Industrial mining began here in 1690,
And it took almost 200 years
To create this huge hollow shape.
All the miners' hard
work would set the stage
For a modern-day transformation
that no one could have expected.
The base of the mine is
370 feet below the surface
And 250 feet across.
Due to the gradual infiltration of water
Through the porous salt walls,
A 25-foot deep underground lake has formed.
Blocks of salt that failed
to reach mining standards
Were thrown back into the terezia mine.
Over the years, it's formed
this impressive island
That now stands 16 feet above the water,
And what the island has
been turned into today
Would shock the original miners
Who worked tirelessly
under harsh conditions.
As the mines grew deeper
and deeper over the centuries,
The walls became so heavy
They couldn't hold themselves up.
Reinforcements became necessary.
900 years ago, workers in this mine
Began using spruce wood in all their beams,
Supports, and equipment.
They discovered its loose-grained
structure absorbed salt,
Creating a layer that prevents
the wood from decomposing,
And in present times,
They're still finding innovative
subterranean uses for it.
For centuries, workers continued
to dig deep bell-shaped mines.
However, excavating large
amounts of salt from the bottom
Was time-consuming and inefficient.
So after 800 years of
digging down in this way,
Miners realized in the 19th century
That by digging horizontally,
The salt could be more
easily and quickly extracted.
A new way to mine salt was invented.
Salina turda salt mines
have been at the heart
Of this region for centuries,
But in 1932, salt excavation ended here.
To this day, engineers
continue to ensure this incredible
Underground space remains relevant,
And in 2008, a radical
transformation took place
The likes of which the
world had never seen.
Narrator: In historic romania,
Home of transylvania
and the dracula legend,
Salt has been mined from salina turda
For more than 900 years.
Up until 1932, workers
excavated the commodity
From a 1-mile-thick layer of salt.
♪
There are still secret places
to which few have access.
From the highest point
above terezia mine...
...To the deepest, darkest
depths of the neighboring
And abandoned bell-shaped josef chamber,
Where the remnants of the
mining work can still be found,
Something no tourist will witness.
[ echoing voices ]
[ echoing ] hello!
Yet in 2008, one of these giant spaces
Was transformed for the future.
In an unprecedented move,
The world's first underground
amusement park was created.
Within this cavernous realm,
mini golf, bowling, handball
And soccer, badminton, billiards,
And table tennis offer a unique experience
To which no other amusement
park in the world can compare.
♪
There's also a 180-seat amphitheater
For conferences and concerts...
...Plus the most spectacular
attraction, a ferris wheel.
Standing at an impressive 65 feet high,
The ride is the world's first
underground ferris wheel
And offers a unique vantage point
For mining experts edmond and paul-florin.
Popa: The size of the chambers
Was the thing that really surprised me.
So you have no idea when you're above
That, underneath your feet,
You have an underground
world like this one.
♪
The ambition of romania's new underground
Entrepreneurs means
salina turda's past and present
Have been seamlessly combined
For the benefit of generations to come.