Original subtitles

[narrator] A desert canyon where fortunes were made

and fates were sealed.

[Auerbach] There's not much here besides desert and rock.

What would draw people here?

Well, in these remote, inhospitable locations,

the answer is usually the same, money.

[narrator] A rural area in Poland that connected the world.

[Meigs] A lot of the electronics are still here.

This two-megawatt transmitter, which is just unheard of.

This two-megawatt transmitter, which is just unheard of.

That's enough to power a small town.

[narrator] And an Island fortress with an Achilles heel.

[Bell] It was armed to the teeth

with guns, cannon and anti-air defense,

but all these guns were useless

against the main threat of that time.

[narrator] Decaying relics.

Ruins of lost worlds.

Sites haunted by the past.

Their secrets waiting to be revealed.

[dramatic music playing]

[narrator] The wilds of Nevada.

In an inhospitable desert

In an inhospitable desert

are the haunting remains of a settlement.

[Bell] This'll places only a 45-minute drive from Las Vegas,

but it feels like a million miles away from the casinos,

the bright lights and the glamour.

[Jerram] When you can see that there are

a number of man made structures around this

and large tanks, there's bits of machinery.

[narrator] Old wooden buildings harken back to the 19th century,

[narrator] Old wooden buildings harken back to the 19th century,

but scattered on the site

are the remnants of the 20th.

There's this rusting old abandoned truck,

a crashed plane.

This place looks like

it's trapped in some type of time warp.

[Bell] This is a wild place.

If the climate doesn't get you, then nature will.

Humans were never designed to live in a place like this.

Humans were never designed to live in a place like this.

[narrator] The site is filled with decaying machinery,

but its purpose is obscured.

[Jerram] If you're gonna go to somewhere so extreme,

you have to be drawn by something.

And usually in places like this,

it's something to do with what's in the ground.

[Werly] This entrance had been covered up for 80 years,

but when we popped into this thing,

there's a half a mile of tunnel in here

that nobody that had been in for years and years.

that nobody that had been in for years and years.

[narrator] People came here seeking their fortune,

but for some, this would be the end of the line.

[Werly] There's nine different levels in here.

There's three miles of tunnels and it goes 600 feet deep.

[narrator] Tony Werly first came to these tunnels 25 years ago.

They were dug in search of a precious mineral.

This is an extremely hard rock.

This is like number seven hard from one to ten.

This is the seven which is stronger than cement.

[Bell] To come here, you need a pretty good reason.

And in the most extreme locations like this,

that's usually to make money.

[narrator] Thing they were looking for was glistening white

and hardest stone.

[Werly] This is a vein.

You can see it runs from here all the way over into here.

You can see it runs from here all the way over into here.

You can just see, it's running up the mountain.

[narrator] This white rock was the source of untold fortune.

The first person to recognize its value

was a man called John Moss.

John Moss was your classic frontiersmen.

They really should be making movies about this guy.

[Bell] He was the first non-native

to descend the Colorado River rapids by raft.

He spent three and a half days being drenched,

He spent three and a half days being drenched,

ducked and pounded by the river

as he traveled through the Grand Canyon.

[narrator] Moss, originally from Utica, New York,

was on an expedition into Western America.

[Auerbach] He apparently had a real gift for languages,

and he spent a lot of time traveling around

with almost two dozen different Native American tribes,

which allowed him to immerse himself in their culture.

[narrator] He was drawn to Nevada by rumors

[narrator] He was drawn to Nevada by rumors

of that strange white rock in the mountains.

He suspected it was Quartz,

a mineral that forms in veins

when hot magma interacts with groundwater.

Quartz is SiO2. It's Silica.

It's one of the most abundant minerals on the planet

It can occur in certain different ways

as these veins rich in Silica, they're rich in other minerals

like lead, zinc, silver, and sometimes gold.

like lead, zinc, silver, and sometimes gold.

[narrator] Moss analyzed the mineral and confirmed his suspicions.

This is Eldorado Canyon,

home to the richest gold deposit in southern Nevada.

[dramatic music playing]

Once the miners found this white coarse vein, they never left track of it.

They'd just keep it in sight, and so they'll chase it wherever it goes.

[Jerram] As you go into the mountain, the geology changes.

[Jerram] As you go into the mountain, the geology changes.

Maybe your vein suddenly goes off on a different angle,

so you follow that, if that's where the where the potential resource was.

[narrator] Following the trail of quartz, however,

was only the first part of a complicated process.

It's important to note here they're not finding big gold nuggets.

In this situation a lot of the gold is small particles in the veins.

[narrator] Carts filled with quartz were pulled out of the tunnels.

But extracting gold from Quartz was expensive and potentially deadly.

[Werly] You have to crush this rock up as fine as you can,

all the way down to the texture of flour.

[narrator] They then mixed crushed quartz with an unfriendly chemical.

It would mix it in these big Cyanide tanks here,

and the Cyanide would pull

the microscopic pieces of gold and silver out of the ore.

[narrator] But with high risk came high rewards.

[narrator] But with high risk came high rewards.

El Dorado was making money hand over fist.

The gold mining that took place in Eldorado Canyon is phenomenal.

About $200 million dollars worth of gold and silver came out of that mine.

[narrator] For every ton of quartz rock, they extracted one ounce of gold.

but the greater challenge was getting that gold out of El Dorado.

but the greater challenge was getting that gold out of El Dorado.

Everything has to be shipped in by water

trucked up the canyon through the Colorado River.

[narrator] In the mid-1800s, there was only one port in and out of the canyon,

a small dock on the river called Nelson's Landing,

[Auerbach] But despite the harshness of the conditions,

despite the difficulty in getting the supplies there,

what's being produced is so valuable

what's being produced is so valuable

that you actually get pretty heavy traffic in and out of the canyon.

And Nelson's Landing turns out to be one of the busiest transition points

for supplies in the whole region.

[narrator] Cut off from the rest of civilization,

El Dorado became a hotbed for criminal activity.

while most of the U.S. was under prohibition,

here, a black market thrived.

It's said that the alcohol produced there for pennies

It's said that the alcohol produced there for pennies

was actually sold for up to one dollar a gallon just across state lines.

[narrator] Nelson's Landing had turned into a Pirate's bay.

It's a shift that would transform El Dorado

into one of the most dangerous towns in America.

[narrator] In the 19th century, a desert gold mine had become

a cesspool for smugglers, claim jumpers and murderers.

Back in the late 1800s, Eldorado Canyon

was one of the most violent and lawless places in America.

[Werly] Yeah, it's a bad place to be. In the 1880s, not even killing is a good reason

[Werly] Yeah, it's a bad place to be. In the 1880s, not even killing is a good reason

to bring the sheriff out here 200 miles away,

He tells them they have to fend for themselves out here.

[Auerbach] A local miner, John Riggs, later wrote,

"I never think there was another place

in proportion to the population where so many murders were committed

and the perpetrators never brought to justice or even apprehended."

[narrator] Greed, vice and murder made El Dorado Nevada's first sin city.

[narrator] Greed, vice and murder made El Dorado Nevada's first sin city.

But it wasn't the long arm of the law that finally brought it down.

When World War II started, All the miners that worked at the mine went to war.

It's been right here, is where they were when they left.

when they came back from World War II, they never opened this mine again.

[narrator] It said that there is still

a million dollars' worth of gold in the Eldorado mine,

a million dollars' worth of gold in the Eldorado mine,

but now it would cost two million to dig it out.

The mine has been silent for 80 years,

but on the surface are the wrecks of military vehicles

that suggest the drama continued.

Hollywood came to Eldorado to film 3,000 miles to Graceland.

Big names, a big budget car chases and a crashed plane.

Big names, a big budget car chases and a crashed plane.

But it was a bomb but good film or bad film,

the legacy remains, and we see it before us now.

[narrator] Hidden in plain sight on the southeast coast of Malta,

is a facility standing guard over the shore.

[Wawro] You've got azure seas. Rocky, sandy beaches.

You've got these tall cliffs rising out of the sea.

[Nusbacher] And as your eye follows these rocky cliffs,

your eye suddenly realizes that you're not looking at a cliff anymore.

Look at those bars on the windows.

If I didn't know any better, I'd think this is a place designed

to lock up the most desperate criminals.

to lock up the most desperate criminals.

It has an almost prison like quality and yet given its placement

right on this important coastline, that argues that this is probably a fort.

[narrator] Viewed from above, distinctive features

confirmed this complex was all about defense.

Here we can see elements of a fortress that date back years,

but we also see elements better, clearly modern.

but we also see elements better, clearly modern.

That are clearly meant to withstand 20th century weapons.

[Wawro] I mean, think about all the Greek, Italian, Spanish islands

that are fortified.

Why is this island fortified?

It must have some real strategic importance.

[narrator] This site was once ready to face a colossal naval assault.

But who was the enemy and did those inside live to tell the tale?

But who was the enemy and did those inside live to tell the tale?

The story of this site

dates back to 19th century, with Malta under British rule.

Matthew Balzan is a local historian

who has explored every inch of the complex.

[Balzan] Here we are in tunnels below the main site,

which run all the way across.

From outside, one would not realize what lies beneath here.

[narrator] While most of what remains above ground was built later,

the original defensive capabilities of this site were hidden from view.

Here, we're seeing an example of a 12.5-inch,

38-ton rifle muzzle loading gun.

The time when it was put in place here in 1880,

was the largest example of rifle muzzle loading technology

the British Army had at its disposal.

Comparing it to the size of a human being

Comparing it to the size of a human being

one can immediately realize the sheer size of such artillery.

What's more interesting about these examples is that these are the last

remaining examples in the whole world, where we still see the original gun

on its original carriage on platform in their original locations.

[Wawro] This represents the acme of gun technology of the time.

It's rifled, meaning it can fire accurately at a much longer range.

More penetrating power, fires a bigger shell with far greater accuracy.

More penetrating power, fires a bigger shell with far greater accuracy.

Its purpose is to kind of spar and jab with assaulting fleets.

[narrator] One of these guns alone, however, would not have been enough.

As the multiple openings in the cliff suggest,

half a dozen of these beasts were once trained upon the horizon.

One can just imagine the sound which would be created

when a gun of this size would be fired.

But to give just a small example,

a gun powder cartridge when fired inside the chamber of this gun

with expanding volume 20,000 times...

and all of that has to go out and smoke and noise.

[narrator] Located just a few miles south of the capital city of Valetta.

This is Fort Delimara.

So, with the guns at the ready,

who would dare to invade?

who would dare to invade?

[narrator] In the late 19th century, Fort Delimara

was built to plug a gap in the main island's defenses.

The British. They learned some valuable lessons from Malta's past.

They learned, for example, that is not enough to fortify

the Grand Harbor around Valetta.

You have to always fortify this secondary harbor.

Marsaxlokk is at the end of the island.

But what had happened previously is everybody had fortified

But what had happened previously is everybody had fortified

the Grand Harbor and left Marsaxlokk undefended and powers like the French

had just sailed in there, offloaded their amphibious forces

and taken the island essentially through the back door.

So what, you see, the British during the 19th century,

is pouring millions into these new fortifications

in this secondary harbor, the Marsaxlokk harbor.

[narrator] Once again, it was the French who threatened to invade.

But now this fort lay in wait.

These massive guns were put here

These massive guns were put here

because this was a desperately sensitive

spot for the Royal Navy to defend.

[narrator] Moats on the landward side, protected it from behind.

But the key to this structure to feeding an invasion force

was in gifting it the element of surprise.

Fortifications are deliberately small

and almost invisible from the sea, They're low profile,

and almost invisible from the sea, They're low profile,

they're pushed up, they're built out of the bedrock,

so they blend into the actual hill itself into the cliffs.

In the olden days, you'd build tall walls to keep people out.

But in the gunpowder age, you've got to build low walls

that are hard to see and that are thick and backed up with Earth.

This is a fortress designed to be effective against modern assault.

This is the very model of modern military architecture.

[narrator] The feared French invasion, however, never came,

and the guns never fired at enemy vessels.

But the threat remained.

In time, a new adversary would appear in the horizon.

[Wawro] From the 1870s, when the British start building

this fort and start adding artillery.

They are continually upgrading the artillery

They are continually upgrading the artillery

as there's changes in casting techniques,

metallurgy, shell construction.

Here, it was the final upgrade to the forts artillery,

The six-inch breech loading gun which was installed here in 1938

in preparation for what would become the second World War.

[narrator] After decades lying in wait,

an invasion of Malta was being planned and this harbor was the target.

an invasion of Malta was being planned and this harbor was the target.

[Balzan] The British military had to be prepared in case of enemy action.

In fact, this gun would go on to be fired in anger during the same conflict

In June 1940, Italy enters the war on the side of the Nazis,

and quickly their ambition spreads beyond Europe.

Malta emerges early on in World War II as a place of great strategic importance.

Why? Because Italy and then Germany are trying to conquer North Africa.

Why? Because Italy and then Germany are trying to conquer North Africa.

[narrator] Under the leadership of Erwin Rommel, known as the Desert Fox,

the Axis powers spread their dominance across North Africa.

with a plan to head east towards the valuable oil fields.

It was while fighting on this front,

that the allied bases on Malta proved their worth.

If Rommel, the great German Tank general, had been able to blast through

If Rommel, the great German Tank general, had been able to blast through

from North Africa to take the caucuses to meet up

with German forces in the caucuses,

then the Nazis would have had the oil,

the resources they needed to keep on fighting

and maybe to keep the war going a long time,

maybe even to win the Second World War.

But for the Italians and the Germans to communicate with North Africa,

to resupply their armies,

they have to be able to freely cross the Mediterranean.

they have to be able to freely cross the Mediterranean.

And they're attacked in this by the RAF

and by the Royal Navy, which are based in Malta.

One of the most damaging raids by the British on Axis' communications

happens in September 1941,

when the British, using their code breaking at Bletchley Park,

they learn of this convoy.

They put submarines right out of his path.

They sink two of these big luxury liners

and German troops are drowned at sea.

Stopping the Nazis at Malta was a way

to stop the Nazis winning the war.

[Wawro] So this is just one small example of the utility of Malta

and why the Germans felt they had to basically crush it out

in order to control North Africa, in order to control the Middle East.

[narrator] The threat posed by Malta was just too much for the Nazis to ignore.

An invasion plan was quickly drawn up,

and Fort Delimara was in the firing line.

and Fort Delimara was in the firing line.

Hitler sees that Malta is really a burr under the saddle needs to be removed,

so, he actually puts together this thing

for 1942, called Operation Hercules.

[Balzan] Marsaxlokk Harbor would have offered a good place to land

because it is a very wide harbor there for accommodating several

hundreds of vessels at the same time.

So, it would allow an easy landing of the enemy force.

[narrator] The Axis plan to combined arial and amphibious attack,

30,000 paratroopers were descended from above inland

while 70,000 more troops would arrive on naval vessels from the south.

Once the forces had overpowered defenses here,

they would continue north towards Valetta.

The Fort here sits at the tip at the entrance of Marsaxlokk Harbor.

Therefore, any attempted enemy invasion

Therefore, any attempted enemy invasion

would have to bypass this location in order to gain access.

Therefore, the Fort was paramount of the defenses of this side of Malta.

[narrator] The invasion was scheduled for the summer of 1942.

The troops stationed here waited with bated breath.

The British forces on Malta were always expecting that German invasion to arrive.

Then at one point they saw a vessel on the horizon.

Then at one point they saw a vessel on the horizon.

Everybody was bracing themselves for the bombardment

that would surely proceed this German fleet.

[narrator] In 1942, Port Delimara was braced for battle.

An invasion of Malta was planned,

and the enemy was soon spotted in the distance.

In August, 1942, searchlights of the Fort

capture the target just outside the harbor

and immediately guns in place here were fired against it.

[narrator] But the target they had cited was nothing like the feared invasion fleet.

Turned out it was an E-boat, the equivalent of a PT boat

that was outlaying minds in the sea off of Malta.

And that gives you an idea of how worried everyone was

that any minute on Malta would be the minute before Malta fell.

But of course, Malta never fell.

[narrator] While Malta had been in the crosshairs,

a change of events on a different front

meant this quarry would never be caught.

Because Hitler gets bogged down in December 1941

at the gates of Moscow,

decides he's going to make a turn in to the Caucasus in 1942

to try to take the oil fields.

He simply doesn't have enough force

to deal with Malta, so he just has to let it go.

[narrator] With the invasion canceled,

Port Delimara continued guarding the southern shores of Malta

until the end of the war.

Twice in its lifetime,

it had faced the threat of invasion

and lived to tell the tale.

In 1964, British handed over Malta to the local government,

and this fort went with it.

Now, it sits silently on the southern cliff tops,

Now, it sits silently on the southern cliff tops,

looking out across the Mediterranean.

In the Polish countryside is the remains of a structure

that history has largely forgotten.

[Wawro] We're in a place called Gawin,

pretty much in the geographical center of Poland.

[narrator] Hidden amongst the trees

is a central building and a lattice tower.

[Meigs] You get the feeling when all this was built, this was open land.

Now the trees have grown up.

A young forest has covered,

a lot of it is hidden some of that.

[narrator] In the tall grass are the footprints of an engineering giant.

[Meigs] You can see other buildings,

you can see concrete pads at some distance away.

you can see concrete pads at some distance away.

Clearly, this was a big operation at one time.

[Bell] It's hard to believe now, but back in the 1970s,

this was a high security location.

[Wawro] Was pretty heavily-trafficked, pretty big site.

And beside it all this wreckage of this,

steel trusses and girders lying in a heap.

[narrator] These scattered elements add up to a greater whole,

[narrator] These scattered elements add up to a greater whole,

but one major piece of the puzzle is missing.

Tomasz Mis is part of a group that protects this site.

We're in central Poland, in a restricted area

of high national and military importance.

We were allowed to get in.

We were allowed to get in.

Nevertheless, very few people are able to do so.

[narrator] Today the building is empty.

All that remains is mold and rust

and solemn reminders of the Cold War.

[Mis laughs] Yes.

Political documents.

[narrator] But there are signs

that this facility required an enormous amount of energy.

So, the site we're currently in

So, the site we're currently in

was extremely powerful, even for today's standard.

[Meigs] One thing that's fascinating at this site, and unusual,

is that a lot of the electronics are still here.

All this stuff looks kind of old and decrepit today,

But it was state-of-the-art back in the '80s.

[Mis] It consumed so much electrical power

that a small city could be powered

using the thing which came in here.

[narrator] Outside the main building

is a clue to what needed that much power.

A concrete anchor designed for industrial cables.

It's a common sight at the bottom of very tall structures.

So, this is the foundation of one of the first level guy ropes,

which held the mast stem in vertical position.

[narrator] Fifteen of these anchor points

[narrator] Fifteen of these anchor points

are scattered evenly across the countryside.

They were used to hold up the Warsaw Radio Mast.

[Meigs] What we're looking at here

is the site of what was once

the most ambitious radio transmitting tower in the world.

It's hard to wrap your mind around how tall this thing was.

2,100 feet,

this was once the tallest man-made structure in the world.

this was once the tallest man-made structure in the world.

[narrator] This tower was designed at a time

when Poles were leaving Poland in their thousands.

One thing that's fascinating about Poland

is how many Polish people don't live there.

They live in all these other places in the world.

By one estimate, there are 20 million people

of Polish descent around the world.

of Polish descent around the world.

[Mis] So after the Second World War,

when the borders of Poland changed

and many Poles actually immigrated also to the United States,

a way of communicating with of them was desperately needed.

[Bell] With such a wide spread community

before the advent of the Internet,

reaching Poles around the world

was a massive challenge.

[Wawro] So, in fact, the polls were looking to set up a radio station

[Wawro] So, in fact, the polls were looking to set up a radio station

in the geographical center of Poland

that could reach Poles all around Poland equally.

But it was also big enough to transmit

to these Polish communities around the globe.

[Mis] Poland had once very powerful radio stations,

which could make contact with them.

But it was not enough,

especially that electrical equipment,

industrial equipment was being built up everywhere.

[narrator] In 1970, they began construction of a new transmission tower.

[narrator] In 1970, they began construction of a new transmission tower.

Switchboards, transformers and guard houses

were all necessary to run the facility.

And in 1974, Polish radio was heard around the globe

through one of the world's most powerful transmitters.

[Meigs] The engineer who designed it was named Jan Polak.

He must have been brilliant.

It was designed in 86 sections,

all joined together

and then anchored to the earth

and then anchored to the earth

with 15 steel, they call them ropes, cables

that would anchor it in any kind of wind conditions.

So when the wind blew,

they would correct for each other, they would stabilize it.

[narrator] The tower stood precisely 2,120 feet tall,

a number that was not chosen by accident.

They were long wave radio signals.

And when I say long, each wave,

And when I say long, each wave,

I mean, a literal wave in the atmosphere

of electromagnetic radiation was over thousand meters.

So why would someone want to use those very long wavelengths?

Because they tend to follow the curvature of the earth,

and they can travel very, very long distance and still be received.

So in the right conditions, signals from this tower

could reach Africa, North America,

could reach Africa, North America,

really just about anywhere.

[narrator] The broadcasts were produced in a studio 60 miles away at Warsaw

before being sent via an intermediary tower

to this radio transmitter station.

They would transmit locally to a radio receiving tower

here near the base of the transmitter,

and that's the big metal structure we see that's still standing.

I mean, it looks big, but it's puny compared to the transmitter.

This tower is approximately nine times smaller

than the mast that was located on the antenna here.

On the top, there's a dish which received and transmitted signals

between the intermediate relay tower and Warsaw.

The main purpose of this tower

was to collect the signal from the Polish radio studios.

So anything, music and speech and all of it.

So that it could be later encoded and broadcast.

So that it could be later encoded and broadcast.

[Meigs] Then they would take that signal and then amplify dramatically

change the wavelength to this long wave system,

and then that's the signal that would go around the world.

[narrator] This engineering giant was Poland's crown jewel.

But today all that remains is twisted metal.

It's a tale of pride coming before a fall.

[narrator] August 8th, 1991,

deep in the Polish countryside,

the tallest structure in the world came crashing down.

The mast broke down, twisted and collapsed

on to the antenna field,

including the exact place where we are standing.

This tower would have been the tallest structure in the world

This tower would have been the tallest structure in the world

until the construction of the Burj Khalifa in 2009.

[Mis] It was 17 years old,

so it wasn't that old actually.

But in fact it needed a desperate renovation

after these 15, 16, 17 years of constant operation.

[Meigs] There's something both impressive and kind of heartbreaking

about this story.

These brilliant Polish engineers built this amazing structure.

These brilliant Polish engineers built this amazing structure.

They put so much love and engineering brilliance into it.

But they were not a country that was able to sustain it.

[Wawro] Building the tallest structure

in the Communist Bloc in Eastern Europe was a pretty dodgy proposition,

considering how just poorly things were maintained.

They were just known for their shoddy architecture, shoddy maintenance.

So in 1991, an attempt was made

So in 1991, an attempt was made

to renovate the mast as it was getting older.

However, the entire process was done

with a couple of major mistakes.

[narrator] A technician was hired to carry out repairs,

but he wasn't qualified for the job.

He detached a major guy rope without adequate support.

[creaking]

The lowest part of the mast fell towards the Helix house,

destroying it, as we can see it here.

destroying it, as we can see it here.

[narrator] Gaslights, designed to warn of air traffic,

had smashed onto the ground, setting off a raging fire.

Some of the bottles with gases exploded as the mast fall on them,

and a couple of fire brigades needed to extinguish all of this.

[narrator] All that was left of the tower

was a medley of twisted steel and broken glass.

was a medley of twisted steel and broken glass.

It was nearly impossible to walk through this area

because it was all covered with the material coming from their masts.

[Wawro] Nobody's hurt.

And yeah, it is a national scandal.

A couple of engineers are jailed for it.

[Mis] This place where we're here now was left largely intact

after the catastrophe took place.

So yes, all around, we can still find many elements of the mast.

[narrator] For Poles across the world,

Polish radio had fallen silent.

Polish radio had fallen silent.

An engineering masterpiece gone before its time.

Today, the site is closed to visitors.

It's probably the biggest and tallest structure on the planet

that most people have never heard of.

[narrator] The Warsaw Radio Mast,

a landmark in the truest sense of the word,

a landmark in the truest sense of the word,

now hidden from view in an anonymous countryside.

[narrator] In Scotland,

near the ancient city of Edinburgh

is a rock that defended a nation.

[Wawro] We're in northern claims here,

and it's an island surrounded by

and it's an island surrounded by

dark cold water at the entrance of a great estuary.

[Bell] It's wet, it's cold.

It's not a place you want to be spending your summer vacation.

[narrator] On this frigid island are empty concrete buildings

and reminders of its former residents.

[Bell] Clearly a lot of people used to live here,

perhaps some kind of commune.

But now it's all overgrown.

But now it's all overgrown.

The only sign of civilization are some chickens.

[narrator] Today, this island is deserted,

but less than a hundred years ago,

it was vital to Scotland's survival.

[Barratt] It's heading into Edinburgh.

Any place like that has a defensive role to play.

[narrator] Two miles out of Edinburgh,

a ferry will take you to a place where few people dare to tread.

The journey crosses a waterway called the Firth of Forth.

It's an estuary that leads into the heart of Scotland.

Gordon Barclay retells how this island became embroiled in a wartime tragedy.

[Barclay] This is the northernmost 9.2-inch gun emplacement.

[Barclay] This is the northernmost 9.2-inch gun emplacement.

There are three of them down the spine of the island

and this is the one that covers the North Channel.

[narrator] This is Inchkeith,

the gatekeeper to Scotland's waters.

During the First World War,

the island was issued with nine new cannon,

capable of firing 6-inch and 9.2 in shells.

[Wawro] Most of these fortifications are built in the early 1900,

1903, 1904, 1905, 1906, 1907

1903, 1904, 1905, 1906, 1907

as they're responding to these fears of German invasion.

[narrator] To defend the Firth of Forth,

the island was made into an impenetrable fortress.

But pure firepower wasn't enough to prevent disaster.

[Barclay] On 4th September, out near the May Island,

HMS Pathfinder was sunk,

went down in a few minutes

and only a handful of men survived out of over 200 crew.

and only a handful of men survived out of over 200 crew.

[Bell] When these guns were put in place,

they were designed to fire on surface vessels,

dreadnought and destroyers.

They weren't built to defend

against anything beneath the waves.

[narrator] The Firth of Forth was breached

Two days before the attack, there was an opportunity to prevent it.

But Inchkeith faltered.

The beginning of the 20th century,

The beginning of the 20th century,

so a new form of warfare.

Suddenly, U-boats and submarines could travel underwater,

could sneak into places that no one had ever imagined.

[Barclay] On 2nd September, 1914, a U-boat, submerged,

managed to get all the way up to the Forth Rail Bridge

by about 10:30 in the evening.

[Barratt] For ages, it was undetected.

[Barratt] For ages, it was undetected.

And then suddenly someone spotted a periscope

sticking up out of the waves and the U-boat left the area.

Two days later, that same submarine surfaced

just outside of the Firth of Forth

and took a shot and sunk HMS Pathfinder.

It's the first sinking by a submarine

in the First World War of a ship.

The Germans then rely all in World War I

The Germans then rely all in World War I

on U-boats, submarines,

that can get past the British blockade

and that can attack British warships, British shipping covertly.

[narrator] This island fortress had failed.

In 1914, there was only one piece of technology

that could detect enemy submarines.

[Barclay] The way the only way to detect a submarine was the human eye.

Binoculars looking out at the sea,

this gray, featureless surface hour after hour.

this gray, featureless surface hour after hour.

And if one spotted the wake of a periscope going through the water,

you were lucky.

Other than that, there was no technology to detect a submarine

or, indeed, to prevent a submarine penetrating a base.

[narrator] Inchkeith was defenseless against the U-boat.

But a line of cables on the rear side of the island

lead to a set of huts that would become Scotland Salvation.

lead to a set of huts that would become Scotland Salvation.

[narrator] In the First World War,

Inchkeith's only defense against submarines

was a soldier looking out to sea,

but it had one major flaw.

[Bell] At that time, there was a lot of hysteria

about new German weapons.

The public were reporting sightings of U-boats

left, right and center.

99% of them ended up being false reports.

99% of them ended up being false reports.

[Wawro] Everybody saw a periscope. Everybody saw a submarine,

so they were just overwhelmed with warnings

of German submarines.

So the British came to disregard them.

So when the boy actually saw clearly a submarine

and reported it, they ignored.

[narrator] Three months after the first U-boat attack,

the Firth of Forth underwent a major upgrade.

A network of new defenses were built between the islands.

A network of new defenses were built between the islands.

[Wawro] Inchkeith is so important

in this anti-submarine war for the British.

They begin, first of all,

by defending the Firth of Forth with anti-submarine nets

that will trap a German submarine trying to come in.

Or it will attach a buoy to the German submarine,

so it will drag this buoy along the surface

and we'll be able to know where it is.

[narrator] But cannon and nets weren't the key to defending Scotland.

The most powerful defenses

were a collection of small huts on the rear side of Inchkeith.

[Barclay] Places like this were vital to the protection of the Firth of Forth.

The men on the gun crews at least were out in the fresh air.

But here you were stuck. hour in, hour out,

day in, day out, watching the instruments.

[narrator] These huts were built on the island

[narrator] These huts were built on the island

as part of a powerful new anti-submarine weapon.

The detector loop.

A submarine produces magnetic field

from its large steel hull.

By laying three cables on the riverbed in a loop,

they could detect the magnetic signature

and send a signal to the guards' huts.

[Barclay] The men listening out for on enemy submarine

had to be somewhere quiet where they could concentrate,

had to be somewhere quiet where they could concentrate,

where there would be no noise to drown out or distract them.

Here at my feet, you see the outlet of one bundle of cables

from detector loops under the river.

Still there.

[narrator] For six years, these huts were never empty.

An officer was always on station,

waiting for a signal that might never come.

[Barclay] There were multiple layers of defense.

A submarine would first be detected

passing the Isle of May

and again by the detector loops just east of Inchkeith.

Parallel with Inchkeith were the mine fields,

which, if a submarine was detected entering them,

could be exploded.

It was pretty impregnable.

As far as we're aware,

no submarine ever penetrated the defenses...

until the final hours of the Second World War.

until the final hours of the Second World War.

[narrator] On May 2nd, 1945,

the first German regiments in Europe laid down their weapons.

They agreed a total surrender to take place six days later.

But on the morning of May 8th,

a U-boat snuck into the Forth.

[Barclay] Two hours before the end of the war,

one U-boat captain attacked a convoy

one U-boat captain attacked a convoy

leaving the river out towards the Isle of May

and sank two ships,

killing a number of men.

[narrator] Inchkeith had failed again.

German U-boat gets in mainly because the British are napping.

They think the war's over.

It's the last day of the war literally.

[Barclay] He claimed that he had not received the order to stand down.

He had, however, been one of the officers

responsible for developing the new type of submarine that he was commanding.

responsible for developing the new type of submarine that he was commanding.

And to my mind, he ignored his orders

and decided to try out his new toy,

his murderous new toy.

[narrator] Fort Inchkeith began with the first submarine sinking in World War I.

It's watch ended with the final sinking of World War II.

[Barratt] June 1st in the Second World War.

The Firth of Forth really

was this incredible series of fortifications,

most of which you are completely unaware of

when you go and see this beautiful area.

[narrator] Now, few people cross the Firth to visit the island.

What was once the frontline in the defense of Scotland

has become a safe haven for the wildlife that reclaimed it.