Original subtitles

Tom ward (narrates): A confounding facility in new Mexico

caught up in a race to save lives.

It's this weird mix of 19th century bridge building

and 21st century 'buck Rogers' kind of thing.

The search for the location of a highly classified spy mission

in Gibraltar.

There have been rumours

that secret caves had been deliberately covered up

and hidden away.

An Estonian base with an explosive story.

This is a mystical island shrouded in Soviet secrets.

And a site in Italy where life was forever on the edge.

There's always been an air of danger around this town.

Decaying relics...

Ruins of lost worlds...

Sites haunted by the past...

Their secrets waiting to be revealed.

Their secrets waiting to be revealed.

At the gateway to the mediterranean on the southern tip of Europe

is a much coveted rock.

It's a piece of land sticking out of Spain,

but it's not owned by Spain.

All around are signs that it has long been fought over.

If you make it to the top of the rock,

you'll find two enormous guns pointing out to the mediterranean.

This place was important enough

to defend with some serious fire power.

But below ground, the real secrets of this rocky outcrop

have been abandoned and hidden for more than half a century.

Have been abandoned and hidden for more than half a century.

Gibraltar had been a place of strange rumours,

that there were these many secret tunnels.

It is grim.

The air is thick with bugs.

If you're fortunate enough to have a torch with you,

you just might be able to see

glimpses of rusting machinery inside.

This is a dark, nasty place to be.

The top secret operation planned for this grisly dungeon

would require sacrifice and service way beyond the call of duty.

Gibraltar aka the rock

is a British overseas territory.

Maintaining control of this strategic peninsula

has been a centuries' long struggle.

Well, to say Gibraltar was well armed

well, to say Gibraltar was well armed

is a bit of an understatement, Gibraltar was extremely well armed.

Local historian Pete Jackson

was once a gunner in britain's royal artillery.

He was stationed on Gibraltar.

What we're gonna walk to now is a 9.2 inch gun,

this capable of firing a shell 3 miles into Africa.

The rock overlooks the 8 mile wide straits of Gibraltar

and sits opposite Morocco.

Gibraltar is a very key piece of real

estate and essentially whoever controls Gibraltar

controls the mediterranean.

It's been a vital British military base since 1704.

They turned the place into a fortress.

With thousands of soldiers, guns,

with thousands of soldiers, guns,

canon, cavalry, and Navy backup.

When you see the size of the shell this thing fires,

you won't want to be on the receiving end of it,

this is going to put the ship down.

One of these things through the side,

the ship is not going to survive that.

But with the constant threat of attack,

the British needed more than brute force

to maintain their grip on Gibraltar.

And the secret to their success lies hidden in the rock itself.

The towering limestone monolith

hides a labyrinth of spectacular caves and natural tunnels...

And there's also evidence of human activity below ground.

You see the original drill marks as it's all being made in the 1700s.

The tunnels that we're in now date from 1782.

This is when we started to dig in to defend against attack.

This is when we started to dig in to defend against attack.

Back then, British defenders needed the tunnels

to survive Spanish assault during the great siege of Gibraltar.

And centuries later,

when Adolph Hitler came to power in 1933,

the value of Gibraltar was not lost on him.

Hitler had hoped to convince Spain to join the war on his side

and of course if he could offer Franco Gibraltar,

that would be a massive incentive.

The British knew of Hitler's ambitions

and that the age old tunnel system

would be crucial in defending the rock.

British commanders in Gibraltar began to develop

an extensive set of underground tunnels

utilising those that had existed before...

And developing a whole extensive network.

What we're in here is called the great north road

and what it is is more or less a main supply route

within the tunnels

and this was big enough before all the pipes

were fitted to drive a 4 tonne truck through.

The great north road is literally given its name

after the great north road in britain

and you'll see as we move along it,

you enter from maida vale in the south,

turning to the north you get to peterborough,

we then get to doncaster and then on to durham.

The reason for this was to allow young conscript miners

arriving from the UK

the ability to quickly orientate their selves to the system

that they were in.

The royal engineers carved out around 20 miles

of new tunnels

to provide bomb proof accommodation

for britain's Gibraltar defence force

which had doubled in size.

So, they tripled the length of these tunnels,

so, they tripled the length of these tunnels,

this new space had room for weapons, ammunition,

housing about 16,000 soldiers,

they had hospitals, communications,

all within this mountain.

Even so, at the start of the second world war,

Hitler's forces looked set to capture Gibraltar.

So, the British devised

an extraordinary intelligence operation

that would spring in to action when the German's invaded.

It was so highly classified

that little is known about it even today.

For decades, there has been rumours

that the rock of Gibraltar had these secret caves and rooms

that were deliberately covered up and hidden away.

More than half a century after the war ended,

the long lost bunker had still not been found.

But the hunt continued.

But the hunt continued.

For many years, historian Phil Smith

has been exploring Gibraltar's tunnels.

In 1997, a group from the local caving club

sat down just outside here

and felt wind coming through from behind a corrugated iron sheet.

When they removed it, they found cast concrete

and as they moved further up they found a small

entrance that leads to this room here.

Until the discovery of these rooms,

the top secret British intelligence operation

had been little more than conjecture.

The first time I was bought in to this room,

I was absolutely amazed,

I just couldn't believe here hidden away inside of the rock

would be a room like this.

What's unusual about this room

is there aren't any windows anywhere.

There's a door on that side,

there's a door on this side

there's a door on this side

but all the rest of it is just solid wall and ceiling,

so a very strange place.

This clandestine complex was the base of operation tracer,

an audacious British mission

to be activated when Hitler conquered Gibraltar.

Operation tracer was the brainchild

of head of naval intelligence admiral sir John Godfrey.

If Gibraltar fell the British would need information

on what the enemy were doing

so the plan was to seal six naval personnel in this chamber

with enough supplies to last them

so they could observe and report back on enemy movements in the area.

The discovery of these underground spy base

finally proved the existence of operation tracer.

The six volunteers would be entombed within these rooms

for the duration of the war.

For the duration of the war.

With this 6 inch crack as their only window.

There was a 10,000 gallon water tank...

Food supplies for up to seven years...

And the all important communications room.

From here they would spy on Germany military operations

and radio their findings to London every night.

The floor was covered in cork tiles to dampen sound.

They couldn't afford to make a lot of the noise,

so we got the cork tiles on the floor

and the door would have been sealed up

and they've got a wall on the outside

leading to the tunnels,

so all those things would help to keep the area quiet.

And a hand cranked generator was installed to power the radios.

In the '90s, the cavers found this strange contraption here,

you can see the blades on it like a propeller,

but there's also a handle here,

but there's also a handle here,

so it looks like it was hand operated.

It could provide electricity

and being operated by hand

it would give the men a bit of workout,

a bit of upper body training to keep them fit and healthy.

So, now we know why there's two toilets here.

Six men potentially sealed in this area for up to seven years,

if you just had one toilet

and it broke that would be a very serious problem for the men.

So, this along with other things in operation tracer

was always a belt and braces

with something to support the primary object.

In a remarkable act of bravery,

these men would be walled into this underground complex

for the duration of the war.

We're not talking about a couple of days or weeks

or even months.

Years of hiding out in utter darkness,

you'd really have to be a person

that was truly committed to the cause

and one who had high levels of mental toughness.

And one who had high levels of mental toughness.

Operation tracer was brilliantly conceived

if the people involved were carefully selected and trained

I think it would guarantee success.

The concept came

from head of naval intelligence rear admiral John Godfrey,

it's a brilliant plan

and if it all seems slightly James Bond,

then what you should bear in mind

is that one of John Godfrey's assistants was a young naval officer

called Ian Fleming

who later went on to write the James Bond novels.

In the end, Hitler did not attack Gibraltar

and operation tracer was never activated.

And when the war was over,

the undisclosed complex was surreptitiously sealed up.

Today, the British still control Gibraltar,

today, the British still control Gibraltar,

but for how much longer?

Gibraltar is one of those places left behind

as not quite ruins of empire but something like that.

But now that britain is retracted

and no longer thinks of itself as an empire,

what place does Gibraltar hold?

The badlands of new Mexico are as remote as it gets.

Yet someone has built here.

Inside this open desert

is a construction that looks like

it's from the 19th century 'wild wild west'.

There's a sort of bridge to nowhere

that runs off of the ground level, on to this platform.

When you get closer,

this place gets actually more complicated.

This place gets actually more complicated.

It's constructed almost entirely out of wood.

But at the same time,

you've got all this clearly modern technology around it.

A bird insignia could be a clue to what went on here.

And despite appearances this creaking structure

is part of a wider landscape that has had global impact.

The deserts of new Mexico

has a very high pedigree for world changing science.

It was here that the first nuclear bomb was tested.

So, what was this ramshackle wooden construction built for?

The origins of this site

relate to an unprecedented event back in 1962.

The launch of telstar 1.

The launch of telstar 1.

The world's first communications satellite.

Telstar was a real watershed moment of the 20th century.

It was a satellite

that was able to broadcast television signal

from space for the first time ever.

But seven months after telstar launched,

it shut down

and it wasn't immediately obvious as to what went wrong.

Today scientists like lieutenant colonel Jeff heggemeier

of the us air national guard

only know what happened thanks to this crumbling structure

out in the new Mexico desert.

Once a highly restricted military facility.

So, telstar 1 went offline

because we were doing nuclear testing in the pacific.

Once that bomb went off,

it created the first ever electromagnetic pulse.

An electromagnetic pulse, or emp,

is a burst of electromagnetic radiation.

A nuclear explosion causes an emp

because it excites electrons in the ionosphere

which then cause an electromagnetic pulse.

Nuclear electromagnetic pulses cause

damaging current and voltage surges...

Which interfere with electronics in susceptible devices.

From mobile phones to aircraft

to satellites like telstar 1.

An electromagnetic pulse attack today

would decimate the technology we now depend on.

Emp was a real national security threat back in the 1960s.

But today an emp spike would still be devastating.

Emp was such a threat to the American air force

because our aircraft relied on these electronic systems.

It just wipes out the technology,

it wipes out the ability to respond to an attack.

So, america needed a way to make its aircraft emp proof

and therein was the engineering challenge.

The wooden relic at this site

is what they used to subject us military aircraft

to the electromagnetic pulse

created during a nuclear attack.

It's all that remains of a classified testing facility

codenamed atlas one.

So, simulating an emp for an airplane in flight

is not practical, nor is it really safe

because if you affected the electronics,

because if you affected the electronics,

you could potentially cause the airplane to have issues

while in flight.

The structure was made out of wood

because if it was metal,

it would affect the electromagnetic pulse we were trying to simulate

and so the solution was to build the world's largest wooden structure

in the middle of the desert.

The design they came up with was inspired

by those old railroad trestles,

hence the name of the structure was trestle.

But the structure couldn't be too high

or they wouldn't be able to get the

100 tonne $300 million aircraft onto it.

The hole in the ground idea was to take a natural hole

and dig it out a little bit more

such that we could put the trestle inside of it.

The idea was to roll the plane off of a cliff

on to a platform,

on to a platform,

so finding the hole in the ground was the easy part.

The difficult part was being able to design this platform

with all of the specific specifications.

That was the job of scientists like bill prather.

My role with atlas one

was as a member of the engineering design team.

Bill knew that the damaging electromagnetic pulses

created by a nuclear blast

would wipe out the electronics in American military aircraft.

But how were they able to simulate such an explosion

on this rickety looking structure.

It's hard to tell from a distance,

but if you look closely,

you'll see these cables that look like powerlines

that are running on either side of the platform,

those are incredibly important

to how atlas one actually worked.

The wedge building on this side

was used for the instrumentation

that recorded the currents measured off

of the aircraft and on either side

are high voltage generators

that generate the emp.

8 million volts on each side

and it drives the pulses on to these wire plates,

one on this side and one on the far side over here,

generating the emp across this way where the aircraft is parked.

We had to do that

because we couldn't use nuclear weapons,

so, we simulated it with high voltage equipment.

Basically, this plane was just inundated

and just bombarded with emp and then after that,

they would turn off the machine, get in,

they would turn off the machine, get in,

put the key in the ignition, and see if the plane still turned on.

This was cutting-edge technology at the time as well

and they couldn't really tell

if it was going to work

until they ran their first test.

The emp pulse from an enemy nuclear attack

would put millions of lives in danger,

so, they put their trust in scientists and engineers.

We knew the structure was good and we knew the concept

would generate the emp.

When they were ready for their first test,

they rolled the aircraft on to the platform

and then they turned on generators which then fired 16 million volts.

As the structure was blasted with the massive current,

to bill's relief, it worked.

It was the first of many atlas one experiments

which showed the us air force how to shield electronics from emps.

Which showed the us air force how to shield electronics from emps.

We then added protection to the plane to stop

that electrical energy from getting through into the plane.

Atlas one really helped the military make leaps forward

in terms of emp resistant circuitry.

By making certain that aircraft could still fly,

even after being hit with emps, we were able to make sure

that mutually assured destruction stayed in place.

And that's an important piece in keeping the cold war cold.

In 1991, with the cold war at an end,

the atlas simulator was finally abandoned.

But the efforts of bill prather

and the atlas one engineers certainly did not go to waste.

And the atlas one engineers certainly did not go to waste.

The thing about emps is they haven't gone away.

Our cell phones, our electrical grids,

all these things would just be completely wiped out.

In the aspromonte mountains of southern Italy,

the shell of a town looms above an inaccessible land.

The town follows the contours of the hillside,

winding down all the way to the river at the very end.

There are multiple levels of houses stacked

on top of each other in places as many as five stories,

all overlooking this deathly drop.

Its desolate streets are paved with the husks of homes

and businesses.

There were stacks of gas cannisters, the

there were stacks of gas cannisters, the

remains of an empty bakery, and even a solitary woman's shoe.

Floors have given away and fallen through,

this place is teetering on the edge of total collapse.

A river bed full of curiously large boulders and scars

on the surrounding hillsides could give an insight

into what left this place deserted.

You wonder if whatever happened here

was completely natural or if there is something else

that could have happened to make everyone leave.

When this village died,

a unique and ancient culture died with it.

The ghost town of roghudi vecchio sits in a precarious position.

The name roghudi derives from words meaning full of crevasses

the name roghudi derives from words meaning full of crevasses

or just harsh and looking around here

you can really understand that.

But that's not the most interesting thing about its name.

Its name is actually Greek, but we're in Italy.

Roghudi is so cut off from the world

that many don't use Italian here but a dialect of ancient Greek.

Former resident Bruno stelitano is one of the few

who can still speak this rare language.

(Speaks foreign language)

The people of roghudi claim origins

that trace back thousands of years

that trace back thousands of years

to the ancient Greeks.

In the 8th century bc,

the Greeks established colonies along the nearby coastlines

of the black and mediterranean seas.

Many ancient Greeks moved

to the coast of Italy

where they founded trading ports.

But over the centuries,

invasions by coastal raiders forced these Greek speaking people

to retreat into the mountains to fortress villages like roghudi.

Not only did this keep them safe

but it preserved their culture from outside influences

for many years to come.

Isolated in this harsh landscape, for centuries,

they clung to the traditions of their Greek ancestors,

some of them eerily foreshadowed the future.

Not far from the village, there's this strange rock

that has confused geologists for years.

That has confused geologists for years.

No-one can quite tell if it's naturally made or man-made.

Supposedly an ancient dragon lived under this rock

with a hoard of treasures taken from bandits and thieves.

The residents of roghudi even sent their priest to feed

the dragon to keep it from destroying their town.

When the priest died, there was no-one to feed the dragon,

it's said that it was so angry that it Rose up

and created landslides for the rest of the town.

The rugged terrain that had once kept them safe would in the end

be their downfall.

This region was prone to earthquakes

and there are two earthquakes that occurred,

one in 1905 and another one in 1908.

The earthquakes rocked the whole of southern Italy.

(Speaks foreign language)

And the river valleys that cut through this region contain evidence

of an altogether different threat.

The reason why the riverbeds that surround the town are so wide

is because when the winter rains and the spring fall comes,

it creates these raging torrents.

As all of this water rushes through the landscape,

it scours the riverbed and everything in its path.

As the water courses down, it causes mudslides

that send boulders powering down towards the riverbeds,

putting the mountaintop villages in serious danger.

In the 1950s, a series of flash floods threatened

in the 1950s, a series of flash floods threatened

to wash roghudi away.

The villagers clung on,

but two decades later,

they weren't so lucky.

In 1971, there was an unprecedented storm.

The saturated ground caused

the slopes beneath the village to move.

(Speaks foreign language)

There was a real fear that the entire town

could have come crashing down hundreds of feet at any moment.

On 16 February 1971,

the town's mayor ordered an evacuation.

The entire population of 1,600 people

were forced to pick up everything they owned and leave.

Were forced to pick up everything they owned and leave.

It seemed the freak rainfall was not the only thing to blame

for the destruction.

Although the floods definitely weakened

the town's foundations, there might be more to this story.

In the 1940s and 1950s, the inhabitants decided

that they wanted to install running water

and a sewer in the town.

Some locals believe

that this may have had unintended consequence.

(Speaks foreign language)

When the floods hit in 1971,

it's possible that the new drainage system

had already weakened the ground below the town.

There's a cruel irony in that trying

to bring modern conveniences to their town,

to bring modern conveniences to their town,

they may have signed its death warrant.

Some residents attempted to return over the years

but most stayed away.

And roghudi was left to rot.

Although the people here lost homes and livelihoods,

there was another casualty of the floods.

It was not only the town

that was decimated by these disasters.

They also severely diminished

the ancient greco Italian culture of the region.

Once widely used across the region,

today calabrian Greek is spoken only by a remaining few.

(Speaks foreign language)

Off the coast of Estonia sits a small island with a big secret.

If you look at the island from above,

you can't see much apart from a thick covering

of evergreen forest.

This forest cover is hiding a narrow Gauge railway.

If you follow along this railroad track,

it will lead you to these pretty imposing structures.

The threatening installations are clearly military.

All along the shoreline of this island

are concrete emplacements and they've got no windows.

When you come up to these buildings,

you see all these things scattered about.

And the rusting remains of heavy ordnance

and the rusting remains of heavy ordnance

may explain the absence of life here.

Something dangerous must have been going on here,

this place was once heavily guarded.

So, what was it hiding?

Estonia's naissaar island sits in the Gulf of Finland,

a strategically important stretch of sea.

(Speaks foreign language)

Olar gofman's family has a strong link to this place.

Olar gofman's family has a strong link to this place.

(Speaks foreign language)

He was following in the footsteps of his grandfather Johannes

who had come to naissaar

when it was still controlled by Russia.

(Speaks foreign language)

The island had been inhabited by fishermen and seal hunters

for hundreds of years.

But because of its strategic position,

but because of its strategic position,

it began to attract the attention of major militaries.

You've got Finland to the north,

you've got Russia to the east,

Estonia to the south,

and Sweden to the west.

In the early decades of the 20th century,

tsarist Russia was on the defensive.

(Explosion)

The original defences were built in 1914

when Estonia was part of the Russian empire.

They'd just suffered a humiliating defeat against Japan,

so the empire led by tsar Nicholas ii decided

to build a series of coastal fortifications

to protect st Petersburg.

(Speaks foreign language)

And there are more tsarist constructions hidden

and there are more tsarist constructions hidden

in the woods.

(Speaks foreign language)

Following the Russian revolution in 1917,

naissaar continued under Russian control,

this time under the communists.

And soon olar's grandfather Johannes was one of the only residents left.

(Speaks foreign language)

For the Soviets, the island's dense forest

was extremely appealing.

Around 85% of the island is covered in forest

making it perfect for covert missions.

The Soviets see the location of the island

as an important one, from that place,

they're going to be able to dominate and control the baltic sea.

They spent a lot of time and a lot of energy building

a whole industrial complex there on the island,

under the cover of the forest.

This is the naissaar sea mines factory.

(Speaks foreign language)

It was the largest naval mine factory

in the whole of the baltic,

it had workshops, storage facilities,

barracks, a network of subterranean bunkers,

and even a power station.

These mines were incredibly dangerous,

when one of them exploded in the water,

the shock from it could be felt over a mile away.

Moving such dangerous weapons around the island was no easy task.

(Speaks foreign language)

They could be moved safely, silently,

without having to build up stores

of vehicles and vehicle fuel.

All the sites on the island were connected by rail.

After assembly, these deadly weapons would be transported again

to the harbour and out into the far reaches

of the Soviet union.

Naissaar was fortified yet further

when the cold war intensified and secrecy heightened.

In the 1960s, the Soviets moved beyond mines

and they actually built a missile base.

(Speaks foreign language)

At the end of the cold war, thousands of sea mines

were abandoned here.

They dismantle and disarm

something like 13,000 of these mines.

When you walk across the island today,

you see hundreds, thousands of empty shells

you see hundreds, thousands of empty shells

of these formerly active mines.

But one mystery remains unsolved.

(Speaks foreign language)

Today, naissaar welcomes back visitors of all kinds.

In 1995, naissaar island becomes

a nature reserve, so tourists and hikers can go

and walk on this once forbidden and very dangerous island.

(Speaks foreign language)

Captioned by ai-media ai-media. TV