Original subtitles

[narrator] They're watching you.

More than 6,000 satellites circle the Earth.

Every day, they uncover new, mysterious phenomena

that defy explanation.

From the skies,

the $37 billion treasure trove.

There are so many structures with so many secrets told.

[narrator] The 500,000 square mile cipher.

These markings can explain one of the deadliest periods in human history.

[narrator] And the lost city of the ancient super warriors.

There are all kinds of artifacts

pointing to the fact that this belonged to Alexander the Great.

[narrator] Baffling phenomena. Mysteries from space.

What on Earth are they?

[theme music playing]

February 13th, 2022.

Northeast Poland.

Alex Ritchie is trekking through this frozen landscape,

drawn by codes captured from the skies.

[Ritchie] It's very difficult to imagine

what they would be out here in the middle of a--

of a dense and very remote forest.

[narrator] A laser scan of a nearby patch of woodland

has exposed these markings hidden beneath the tree line.

[Walters] What the lidar has uncovered,

is a series of these huge zigzagging patterns

that appear to be carved right into the landscape.

[Janulis] It's an odd-looking collage of lines.

It almost looks like an abstract painting.

[narrator] Further analysis reveals

the strange shapes cover an area

of one square mile.

[Janulis] The more you look, the more you see.

So what seems to be going on here

is more than just some zigzags.

[narrator] Ritchie moves deep into the forest,

heading for the image coordinates.

Well, the lidar has brought me to this place.

And, well, there is a lot of undergrowth.

This is a-- clearly the foundation of some sort of building.

[narrator] A few hundred feet away, sits another structure.

One that appears to serve a defensive purpose.

Oh, my goodness.

Look at this.

Gigantic...concrete structure.

The walls must be ten feet thick, if not more.

What's so amazing is, as I look around, you can see

that there are more than one of these strange structures

in this forest.

And they're just massive.

[narrator] In total, Ritchie finds

over 200 similar structures littering the forest.

Etched into one of them is a warning.

Here's our clue.

[reading German]

[In English] Which means,

unauthorized personnel are not allowed to go in.

[narrator] The aerial image has uncovered the remains

of what appears to be a vast Nazi compound,

swallowed by time.

It's just extraordinary what remains on this site.

What was this huge complex hidden in the forest?

[narrator] Experts turn to declassify Nazi files.

They reveal something extraordinary.

The critical turning point in German history

occurs at this complex.

[Janulis] These bunkers were the headquarters

of the German Army High Command.

This is where they coordinated and planned

the invasion of Russia.

[narrator] In 1939,

Hitler forms an uneasy pact with Joseph Stalin

to ensure that he will not interfere

with his planned assault on Poland.

But the following year he betrays his ally

and issues an order to invade Russia.

Codenamed Operation Barbarossa.

[Auerbach] This was not meant simply to weaken the Soviet Union.

But to remove the threat

posed by, for all time.

[narrator] In the run up to the invasion,

Hitler constructs the complex in the image

for 40 of his top generals

and 1,500 officers and soldiers.

[Ritchie] So, this was a huge complex.

Like a spider web of power

for the running of the eastern front.

[narrator] In June, 1941.

Three million Nazi troops

and hundreds and thousands of vehicles and planes

sweep into Russia.

The largest, most powerful invasion force in history.

[Cavell] They were hoping the Soviet military would fail.

And fall within ten weeks or less.

But they didn't.

[Auerbach] They miscalculated in one very, very important way,

which is that Russia's never gonna run out of three things.

Land, cold and guys.

[narrator] Fierce Soviet resistance

stalls the German advance towards Moscow.

And by November, 1941,

730,000 German soldiers

lie dead in the sleet and snow of the eastern front.

[Janulis] Operation Barbarossa

was one of the most horrific campaigns inhuman history.

Both, for the attackers and the defenders.

[gunfire]

[narrator] The Nazi's failure

to swiftly overrun the Red army infuriates Hitler

Who takes personal control of the operations at the site in the image.

But the slaughter continues.

Culminating with the Nazis' surrender at Stalingrad.

A siege which leaves a further half a million German soldiers dead.

With the loss at Stalingrad,

Germany loses all of its forward momentum.

From that moment until the bitter end,

Germany is retreating and defending.

[Janulis] It was a war o attrition.

It chewed up the German army and spat it out.

Basically, Hitler blew everything he had

trying to take a country that wouldn't give up.

[narrator] The site in the image

is where Hitler makes his greatest tactical error.

One that ultimately costs him the war.

Yet, as Ritchie continues to explore,

she discovers it's dark secrets don't end there.

Oh, my goodness.

Now, that's amazing.

It's some sort of shaft but I can see

that it leads to a huge chamber, by the looks of it.

[narrator] The Nazi base, it appears,

sits on top of a man-made subterranean world.

It's as if there's a whole underground city here.

What was it doing in this forest

in the middle of nowhere?

[narrator] Coming up...

The hunt for Hitler's gold.

[Janulis] We've only scratched the surface

of what the Germans were up to out here.

[narrator] And terror rises from the wastelands.

If you don't get treatment,

you die.

[narrator] Lured by strange markings in a remote Polish forest,

Alex Ritchie has discovered a vast secret base

used by Hitler for his failed invasion of Russia.

It is littered with hidden chambers and tunnels.

This is not just a city that was built overground.

It was also built underground.

It's not unusual for Nazi bunkers to have underground areas,

but the scale of these underground chambers

is massive.

Why did they need them?

[narrator] Ritchie speculates the chambers could have played

a part in the looting that took place

during Hitler's battles with Stalin.

[Ritchie] The Nazis were greatest looters or arts and artifacts

that the world has ever seen.

And it has always been a mystery as to what treasures were kept.

[narrator] During the Nazis retreat from Russia,

they returned with over one million pieces of art and other treasures.

Pillaged from estates and museums.

Even today, $37 billion worth of their wartime heist

remains unrecovered.

One of the major treasures that we know the Germans stole

was something called the Amber Room,

from the royal palace in St. Petersburg.

This thing was ridiculous.

It was known as the eighth wonder of the world.

[Auerbach] The Amber Room is one of innumerable treasures

looted by the Germans.

The ultimate fate of which is unknown.

[narrator] A gift from a Prussian king to Tzar Peter the Great,

the room's panels are inlaid

with over six tons of amber, gold, silver and precious gems.

[Morgan] It is reported, when you entered the room,

it had this breathtaking quality.

It had a means of dazzling people.

Um, and that's why it was something that was fit for a king.

[narrator] The Nazis dismantle the Amber Room in 1941,

and ship it toward the site in the image

before it disappears from history.

There's a personal account, indicating that a number of trucks

carrying an unidentified cargo

made their way to this bunker complex.

And that they were quickly unloaded.

And the belief is that

maybe the Amber Room can still be found there, to this day.

[Ritchie] This is a really remote and dense forest.

It would be an ideal place to hide something.

[narrator] The role this complex and its hidden chambers

played in the looting of Russia

remains to be discovered.

As Ritchie continues to explore the area,

she finds another mysterious relic of the Nazis' time here.

Oh, my goodness.

Wow.

Now that is something I did not expect.

It's a huge, huge concrete structure.

And yet, what's very strange is that the bottom

is a kind of canal with water in it.

[narrator] Nazi record reveal the giant structure

is a lock, sitting on what's known as the Masurian Canal.

[Auerbach] The Masurian Canal was started in 1911.

When this are was still part of the German Empire.

The goal was to bring trade and prosperity to this remote outpost.

[narrator] The advent of World War I

brings construction of the canal to a halt in 1914.

But two decades later,

work resumes under the command of Hitler.

His aim is to connect the giant lock in the woods

to a nearby river and onwards to the Baltic Sea.

This canal represents, basically, a naval gateway

to anywhere you wanna be in the world.

Why were the Germans building such a large canal system here?

[narrator] The canal's proximity to the Nazi command center

fuels speculation that it may have served a clandestine

and highly controversial purpose.

We know many of the Nazis,

particularly high-ranking ones,

were planning escape routes

at the end of the war.

They could read the writing on the wall.

[narrator] During the closing stages of World War II,

Nazi officials find themselves trapped

between advancing Allied and Russian forces.

Fearing bloody retribution for their war crimes,

many looked to sympathetic nations for protection.

To be captured by the Red army

was almost a guarantee that you would be killed.

So there was definitely a sense of rats fleeing a sinking ship.

[narrator] The canal, when completed,

would provide a naval route

from the Nazi complex to the Atlantic Ocean, and beyond.

This plan, if true, would have seen Nazi officials escape from this region

out to the Baltic, and all the way to South America.

[Janulis] Perhaps, this canal system was plan B,

for this base.

Make your last stand there.

But if everything goes wrong,

you have an escape route.

[narrator] Today, much of this giant complex

and its subterranean chambers

remain unexplored.

Their contents, a mystery.

Eight decades after the war ended

it is an enigma revealed from the skies,

waiting to be decoded.

[Ritchie] There are so many structures in the forest

with so many secrets still to tell.

[Janulis] This discovery is showing us,

That we've only scratched the surface

of what the Germans were up to out here.

[narrator] Coming up...

The mystery ancient mega plague.

Many historians say that this would have been

the worst time in human history to be alive.

[narrator] And a secret rises from the sands.

[Horton] This is a highly significant location.

Because this was the cradle of civilization.

[narrator] October 9th, 2018.

A satellite flying over Asia,

scans the seemingly featureless plains

of Southern Kazakhstan.

And captures this image.

[Munoz] The thing that draws me eye

are these random pitting or scarring marks

on the landscape.

And there doesn't really seem to be any rhyme or reason to them.

The little, kind of, radiating star shapes,

hundreds, thousands, tens of thousands of them,

they're just bizarre.

[narrator] Scientists estimate the mystery pattern

covers half a million square miles.

And area three times the size of California.

And the mystery of this giant desert code

doesn't end there.

Here's where it gets really weird.

Locals who have gone near this area,

report these apple or egg-sized lumps

in their groins or in their neck.

[Kays] Apparently, these are pretty serious,

and if you don't get treated, you can die in a couple of days.

[narrator] Tests reveal the victim succumbed

to one of the most feared diseases on Earth.

One, that by some estimates,

has killed five times as many people

as the ravages of World War II.

[Ruben] Strangely enough, these markings

can help to explain one of the deadliest periods in human history.

The Bubonic Plague.

Also known as the Black Death.

[rats squeaking]

[narrator] In 1347 CE,

the inhabitants of Eastern Europe

begin suffering from mysterious ailments

and pustulating skin conditions.

[woman coughing]

Within five years,

25 million people are dead.

Almost one-third of Europe's population.

[Rice] The bubonic plague burned through Europe,

causing suffering and death

on a truly unimaginable scale.

[Anthony] No one knew where it came from,

or how it spread.

You couldn't treat it.

Many historians say that this would have been

the worst time in human history to be alive.

[narrator] Devastated survivors

irrationally blamed the disease on gypsies,

witches, or Jewish people.

Thousands are tortured and burned to death.

It's not until the turn of the 20th century

that scientists identified the real culprit.

A bacteria carried by infected fleas.

Rats carry fleas.

And the theory was that when plague infects fleas,

the fleas can bite humans, transmitting the disease.

And more rats leads to outbreak like the Black Death.

But there's a problem with this theory.

The latest research suggest that

14th century outbreaks of plague

did not correspond to increases in rat population.

So something else must have triggered these outbreaks.

[narrator] Some scientists now think another animal

is to blame for the mass death.

One that makes it home in the vast steps of Kazakhstan.

This unusual pattern that we see

is actually caused by gerbils.

As they create their burrows

they kill all the plant life above it.

And that leaves these big patches of barren earth

that reflect really well in satellite images.

[narrator] Known as great gerbils.

These rodents grow to around one foot in length

and live in family groups.

Numbering in their millions,

a three acre patch of desert

can contain over 1,000 burrows,

creating vast patterns visible from space.

Gerbils, as cute as they are,

can also be the unwitting host of Yersinia pestis,

the bacteria that caused the Black Death.

[narrator] Scholars believe that Yersinia pestis

originated in this part of the world

some 6,000 years ago.

It persists in the guts of gerbil fleas for centuries.

In the middle ages, this festering, biological time bomb explodes

when the plague-carrying insects hitch a ride westwards.

[camel grunting]

[Anthony] It seems as though fleas from these gerbils

were able to attach themselves to Mongols and their camels

traveling along the Silk Road into Europe.

And that might have been the true source of the plague.

[narrator] What's more...

Fluctuations in the gerbil populations

help explain why so many waves of the Black Death

swept west during the 14th century.

[Kays] Scientists looked at weather patterns

that drive gerbil boom birth cycles.

And what's amazing is those synced up with

really bad outbreaks of bubonic plague in Europe.

[narrator] In the late middle ages,

advances in hygiene and medicine

suppressed the plague in Europe.

In the 1940s,

Soviet authorities try a very different approach

to eliminating the disease in Kazakhstan.

They declare war on the gerbil.

[Rice] They were spraying the burrows with DDT.

They were burning the lands so the gerbil would have nothing to eat.

The Soviet Union was so hell bent on eradicating the plague,

that it actually conscripted thousands of civilians

to take spoonfuls of grain tainted with poison

and pour them into these little burrow holes,

in an attempt to kill off the entire gerbil population.

It wasn't a bad idea but it didn't work.

The gerbils soon came back and brought the plague right back with them.

Because of gerbil populations like the one in this image,

the plague is endemic to 40 percent of the area of Kazakhstan.

[narrator] Today, with the plague still so widespread in Kazakhstan,

images such as this play a key role

in predicting when the next outbreak may erupt from these lands.

Because the gerbil burrows have this recognizable, pale, star shape,

our approach for controlling them could be much more targeted.

[narrator] Death it transpires has many different faces.

[Kays] It's really amazing that this disease,

which has been so important in human history...

That now we can manage it by watching gerbils from space.

[narrator] Coming up...

A secret site that helped change the world.

It becomes the largest single industry

the world has ever seen.

[narrator] And the city built on bones.

[Chamberlain] This is just incredible to think

that this entire city

might have been lost to history forever.

[narrator] June 12th, 2019.

An aerial survey of the Arizona desert

captures this image.

[Walters] This is a rugged, mountainous desert.

And then there's this perfect, elongated, oval

etched into the terrain.

[Kourounis] And within that oval there are other weird shapes.

Including what almost looks like a figure eight

and a few small buildings.

It's the shapes that really get me.

[narrator] Analysis reveals the shapes appeared

to be fashioned from asphalt or concrete.

In total, some 20 miles of these roads to nowhere

crisscross the isolated facility.

This is inaccessible, very rugged terrain.

And yet, clearly, a lot of effort has gone into building this.

Why would you do that?

[narrator] The compounds location could offer a clue.

One really interesting fact about this particular image

is that it's not very far from the Yuma Proving Ground.

[narrator] The Yuma Proving Ground

is one of the largest military test sites on Earth.

A 1,300 square mile laboratory

for testing all most every piece of equipment

in the US arsenal.

A proving ground is just that.

It's a place where you test new things.

The Yuma Proving Ground

has the longest overland artillery range

in the entire United States.

And the most well-equipped helicopter weapons test range imaginable.

[narrator] During tests at Yuma,

troops unleash around half a million munitions a year.

[gun firing]

And drive prototype vehicles over 200,000 miles.

These roadways within this perimeter

could be used to test things like tanks

and other kinds of all-terrain vehicles.

[narrator] However, others think this site doesn't serve a military purpose.

If you wanted to really test how rugged your vehicle is,

why would you pave so many of the roads

in your proving grounds?

Proving grounds aren't just operated by the military.

You also have civilian industries

that need these secure and private locations

to put new products to the test.

I think that this Arizona facility

is the Chrysler Proving Grounds.

[narrator] The secretive facility

has its origins in the aftermath of World War II.

As peace returns to the US,

millions of households go on a spending spree.

In the wake of World War II

there is an explosion in car ownership.

[Kourounis] Americans fell in love.

It was all about how the automobile

represented prosperity and freedom.

[narrator] Between 1946 and 1955,

US car production quadruples.

The 1944 Highway Act

also authorizes the construction

of 40,000 miles of roads.

Replacing rough tracks with paved arteries connected the nation.

You had all this infrastructure popping up

that could support that.

We see the advent of drive-thru restaurants,

drive-in movie theaters.

[Kerley] There is this entire post world culture

that's really built around the car and mobility

And it becomes really a part of the American life.

[Auerbach] The automotive industry doesn't just become

the largest industry in America.

It becomes the largest, single industry

the world has ever seen.

[narrator] The post war economic boom

also fuels an explosion

in the number of people taking vacations.

[narrator] In the 1950s

more than 80 percent of such travel is taken by car.

With each trip averaging 600 miles.

Trips which test these new generation of vehicles

to the point of destruction.

It's one thing to build a car

or anything, for that matter, on paper.

It's another thing entirely to take it out in the real world

driven by real people.

[narrator] During the '50s,

America's car makers construct several sites

like the Chrysler Proving Ground

to road test their latest models.

The large banked oval tracks,

they're typically used for speed testing.

Then in the middle there's a grid.

Now that simulates a city traffic system.

And then there's also access to steep grade mountain roads.

Cars were driven endlessly

around these tracks to evaluate every component

to make sure that it was able to withstand the stress.

[narrator] Before selling the site in 2006,

Chrysler uses the proving ground

to put countless classic cars through their paces.

Cars that go on to define the lives and adventures

of generation of Americans.

These testing facilities were indispensable

for producing the cars that you and I enjoy today.

[narrator] Coming up...

A mystery rises from the desert.

Whatever it is, it's been there for a long time.

[narrator] And a toxic time bomb.

The word apocalyptic comes to mind.

[narrator] In 1959,

the first of 120 Corona spy satellites

takes to the skies.

Over the next decade they capture images

of more than one and half million square miles

of the Earth's surface.

For today's historians,

these declassified images

are an archaeological treasure trove.

They capture imagery of sites that have long since been covered over.

And changed beyond recognition.

Some of these sites have been built on since the '60s.

And so these images give us a snapshot back in time

of what the area would have looked like.

[narrator] When analysts study a 1966 Corona photograph

of Northern Iraq,

they discover something not visible

in modern satellite images.

My eye is drawn immediately to the enormous

rectilinear structure in the center of it.

[Ruben] It has thick walls.

It looks like it's defensive in nature.

Like a fort.

Whatever it is, it's been there for a long time.

[narrator] The location of the mystery structure intrigues analysts.

It sits inside this so called Fertile Crescent.

A vast middle eastern region which was home

to some of the earliest civilizations in human history.

[Horton] This is a highly significant location.

Because it was the Cradle of Civilization.

And the place where urbanism really develops.

[Janulis] This landscape is incredibly, historically rich.

Almost everybody has conquered or have come through here.

[narrator] When archaeologists deployed drones to study this site,

they discover an array of structures,

including a temple and other monumental buildings.

[Chamberlain] When the drones go in,

they find it's not just this one, big fortress.

There are other buildings.

This looks like a large, ancient city.

[Ruben] What we're looking at is clearly a complex settlement

belonging to someone with power.

[narrator] The lost city covers an area

equivalent to 100 football fields.

Excavations suggest it was constructed

around two and a half thousand years ago,

by order of the greatest warrior in history.

There are all kinds of artifacts that are pointing to the fact

that this belonged to Alexander the Great.

[narrator] Born in 356 BCE,

Alexander becomes the kind of Macedonia at the age of 20.

Before embarking on a campaign of conquest without parallel.

Alexander was perhaps one of the most unique

conquerors in history.

His tutor was Aristotle, who made his mind razor sharp.

No one was better suited to conquer the world than Alexander the Great.

[yelling]

[narrator] Deploying revolutionary military tactics

such as the phalanx,

within five years, his forces had vanquished

Greece, egypt and Turkey.

Alexander is just crushing his competitors.

He is dominating the known world,

except for this one other land.

Persia, run by Darius the Third.

[narrator] In 331,

Alexander's 50,000 strong army

advances through the region in the image

before attacking the Persians at the battle of Gaugamela.

[horses neighing]

Deploying fast strike cavalry charges,

his soldiers overcome Darius' forces

despite being outnumbered five to one.

Alexander the Great was a military genius.

He didn't rely on numbers to win wars.

He relied on tactics and strategy.

[Ruben] It's because of victories like this

that Alexander is known as Alexander the Great.

[narrator] Alexander goes on to conquer

a two million square mile empire

and remains undefeated in battle.

The lost city appears to have been built

to ensure his exploits aren't just recorded on the battlefields

but are also immortalized in stone.

One of the ways that Alexander made his mark on

and held the lands that he conquered

was by building vast cities there.

Maybe this city was founded

to celebrate the victory in Gaugamela.

[narrator] The fort discovered in the satellite image

guards a military route into the Persian empire.

It's also a reminder to his new subjects

of Alexander's crushing defeat of their leader.

[Chamberlain] To consolidate the victory,

he builds a city to say,

"Guess what? You are now part of my empire.

Look at me. I'm great."

[narrator] Over the following millennia,

Alexander's city is swallowed by the sands.

Only to be revealed once more from the skies.

[Chamberlain] This is just incredible to think

that now that we have this image,

it's exposed this entire city

that might have been lost to history forever.

[narrator] Coming up...

The mystery mega wound.

We have seen this unusual spike in illnesses

amongst the people that live there.

[narrator] May 26th, 2020.

A satellite above the Caribbean island of Jamaica

photographs something bizarre.

Here we are in an enormous rain forest.

Right in the middle we have this desolate, red patch.

[Kourounis] The word apocalyptic comes to mind

as if it's a giant scar across the landscape.

[narrator] The red stain spreads over one square mile.

[McRobbie] If you look even closer,

you can see that the Earth is,

sort of, pockmarked with these regular circles.

[Okereke] There are dozens of these circles

and they're spread out in these clear rows.

It's really odd.

[narrator] Geologist Devin Dennie

discovers disturbing local reports

that could offer a clue.

One thing we have seen lately

is this unusual spike in illnesses

amongst the people that live there.

[narrator] Since the appearance of the red scar,

countless Jamaicans living nearby

have complained respiratory illnesses and skin conditions.

This spike of illness could be coming

from having more dust in the air.

More red dust.

And that is a sign of what we may be looking at here

is a bauxite mine.

[narrator] Bauxite is the main ore used

to produce 65 million tons of aluminum,

worldwide, each year.

It's also a primary source of gallium.

A rare earth metal of vital importance to tech industries.

For the longest time, we've used silicon in our microchips.

But recent studies have demonstrated

that gallium is more than a thousand times more conductive.

[Okereke] This makes it extremely valuable for use of electronics.

Which is a market that's obviously growing exponentially.

[narrator] Around 367 million metric tons of bauxite

is mined globally each year.

It's importance to the future of the tech center

means that one country is rapidly expanding its interest

in bauxite mining.

The Chinese government is desperate to control the mineral market.

So Beijing has been pouring billions of dollars into poorer nations

with large, natural deposits of these materials.

[cheering]

The plan is monopolize control of rare earth minerals

and not only is that a good economic plan,

but it would give China a tremendous amount of global power.

[narrator] Over the past decade,

China has launched a trillion dollar global development fund.

Of that, Jamaican authorities accept $300 million

in exchange for control of the mine in the image.

What we're seeing from China

is a kind of modern day colonialism.

Instead of invading other nations,

Xi Jinping is flexing his country's economic muscle.

[narrator] Today,

China processes 80 percent of all rare earth elements.

That provides them with a grip over the global manufacturing

of anything from smartphones to fighter jets.

China wants to replace the US

as the next great superpower.

And mines, like the one in Jamaica,

are part of their plan to do it.

[narrator] To extract bauxite,

miners strip vast areas of jungle

before blasting out the mineral rich rock

and crushing it in piles.

[Dennie] That could also be some of the features that we see on the image.

Some of these circles are actual piles of crushed bauxite.

[narrator] As well as releasing vast clouds of dust into the air,

the mine tailings seep into the water supply.

In mining when you extract the material you want,

you also get a lot of materials you don't want.

And those end up in separating pools as waste

that can sometimes be toxic.

Many of the townspeople won't touch the water anymore.

Those who have say that it made the water undrinkable.

[narrator] Globally, air pollution causes

around five and half million deaths each year.

The long term health effects of our tech obsession

on the people of Jamaica remains to be seen.

[Dennie] As long as populations continue to demand

high technology products,

their demand is going to be there.

For more mines like this one.

This red stain in the heart of the Jamaican countryside

isn't going anywhere.