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.

The mystery of the king,

the cult, and the hunt for the Lost Ark.

HORTON: This is one of the most bizarre

things I've ever come across.

NARRATOR: World War Weird.

These lines are part of the battle against

the deadliest foe that the world has ever faced.

NARRATOR: And revealed from the skies,

the ghost town that helped build America.

The entire town was left to nature to completely

reclaim it.

NARRATOR: Baffling phenomena, mysteries from space.

What on Earth are they?

[theme music playing]

February 2022.

Mark Horton is journeying through Ireland,

hooked by something bizarre seen from space.

I'm well intrigued by this image,

and that's why we have to go and investigate.

NARRATOR: The image, captured over County Meath,

reveals a code etched into the landscape.

The hills of Ireland are known for being green and lush.

But here, we have some very unusual

structure hiding in those beautiful rolling hills.

You have these two circles, and they look

like they're sort of raised out of the earth.

NARRATOR: The weird structure appears to be ancient

and measures around 500 feet in diameter.

We know that circular earthen structures built by ancient

peoples have been found elsewhere in Ireland

and Britain,

but what's really weird about these circles is

that they're conjoined in a figure of eight.

NARRATOR: Tales of mysterious rituals in

these lands stretched back for millennia,

a clue, Horton believes, that

the structures once served a ceremonial purpose.

This part of Ireland is absolutely steeped in history,

and I'm really keen

to find out how our site might fit in.

NARRATOR: Horton approaches the site from the north

through two 750-foot-long parallel banks

visible in the image.

These go on and on, as if it's drawing

me up to the center of this sacred site.

NARRATOR: Yet when the archaeologist reaches

the figure eight feature, it's not what he expected.

What I saw in the image was two

neat, intersecting circles,

but it's so much more complicated,

with humps and bumps absolutely everywhere,

kind of like waves in the sea.

NARRATOR: The shapes seen from space are,

it turns out, two mounds surrounded by several deep

ditches and banks of earth.

And at the center of the larger hill

is something not visible in the image.

HORTON: It seems to be a stone.

It's completely smooth.

It's almost...

dare one say it, slightly phallic in shape.

NARRATOR: The monolith has been worn smooth by centuries of

human hands.

And it reminds me a bit of storrs like this on the coast

of Scotland, which were used for inauguration

of their chiefs and their kings.

NARRATOR: Historical records confirm that the structure

was once one of the most important inauguration sites

of prehistoric Europe.

For millennia, it played a key role in the lives

of legendary figures called the High Kings of Ireland.

The High Kings of Ireland are shrouded in mythology

and mystery,

but the evidence suggests that this was a site of supreme

importance for a phenomenal length of time.

NARRATOR: Legend states that some of the earliest High Kings

were crowned here in the 15th century BCE

and that they gained their power by

marrying a goddess.

But it's not until centuries later that

verifiable evidence of these inauguration rituals emerges.

In the early centuries of the first millennium CE,

we know that there were over 100 kingdoms in Ireland,

each competing with one another for power.

NARRATOR: Out of these warring states

rose five principal kingdoms.

A court would then select a chieftain from one

of these realms to be the supreme leader of Ireland,

the so-called High King.

They didn't inherit the throne

or assume it through any divine right.

WALTERS: The evidence suggests that they were often symbolic

figures with this almost kind of godly status.

NARRATOR: The coronation ceremony for each new king

takes place on the site in the image,

called the Hill of Tara.

Before being inaugurated, he must touch the pillar

at its center known as the Stone of Destiny.

Legend has it that the stone would cry out if it was

touched by a true High King,

and that this cry would be heard all over

the Emerald Isles.

HORTON: All these

amazing earthworks on top of the hill

must have underpinned the power and authority

of the High Kings of Ireland.

NARRATOR: For 2,500 years,

the Hill of Tara is one of the most hallowed sites

in Ireland,

where over 140 kings are crowned.

Yet, as Horton consults recent geological surveys of the site,

he spots something close to the giant rings

that doesn't fit with this sacred landscape.

This is

an incredible image.

Most of the site has nice, rounded mounds,

but this bit is quite different.

Something really odd has been going on here.

NARRATOR: The image reveals that, at some point in

the past, part of the site has been repeatedly excavated.

Somebody's come in

and essentially desecrated this sacred place.

I mean, it's all very peculiar.

NARRATOR: An early 20th century photograph of

the event offers a bizarre and disturbing clue.

The people that were digging here was a cultish

group who believed that underneath the Hill of Tara

was buried the Ark of the Covenant, and it's one

of the most extraordinary, weird stories I've ever heard.

NARRATOR: Coming up, the hunt for the Lost Ark.

The Egyptian princess carried it with her from Egypt,

and it was buried on this hill.

NARRATOR: And kill or cure -- history's mystery medicines.

Some of the treatments ranged from

eating spiders to drinking your own urine.

NARRATOR: Lured by mysterious structures captured

from space, archaeologist Mark Horton

is at the Hill of Tara,

the coronation sight for the High Kings of Ireland.

This is the sacred heart of the island of Ireland.

NARRATOR: A 120-year-old photograph reveals that part of

the sacred site has been desecrated by a mysterious cult.

JANULIS: The desecration was actually done

by the British Israelites, who believed

that this was the location of the famed Ark of the Covenant.

NARRATOR: The British Israelites is a movement

founded in the 1840s.

Its members believe that they are direct descendants

of one of the lost tribes of Israel,

as documented in biblical texts.

JANULIS: It's a Christian movement formed by

British people who looked for evidence

to prove that they were one of

God's chosen people.

NARRATOR: The cult's beliefs

appeal to groups of white nationalists

and soon grows in numbers and power.

This idea that the Anglo-Saxons were descended from

a favored Israelite tribe caught on

in the United States, and the impact of this movement

is still being felt today.

NARRATOR: As the cult grows, it creates its own mythology

based on pseudo history and elements of Irish folklore.

In the 1890s, it proclaims that the Hill of Tara

is, in fact, a spiritual capital of the British Empire,

and within it is buried the Ark

of the Covenant and the Ten Commandments.

They had this strange myth that an Egyptian princess

carried it with her from

Egypt, and then she married

a chieftain, and then it was buried on this hill.

NARRATOR: In 1899, the group begins to excavate the site,

creating scars visible in the satellite image.

The desecration enrages many Irish and fuels

resentment of British rule of their country.

HORTON: The sheer arrogance of the British Israelites,

to think that they could come over from Britain

and desecrate one of Ireland's

most sacred and ancient sites.

And so what this did was helped reawaken

Irish Celtic nationalism,

and this led to the Irish revolution.

NARRATOR: The cult's vandalism of the Hill of Tara

ultimately helps Ireland gain its independence.

But the role this extraordinary place played

in this country's history doesn't end there.

There is, of course, no connection whatsoever

between the Ark of the Covenant and the Hill of Tara.

But there is another story, which might

well have a grain of truth in it.

The Hill of Tara also has

an important role to play in

the story of the man credited with bringing Christianity to

Ireland, St. Patrick.

NARRATOR: The story begins in the early 5th century CE.

St. Patrick was a Roman citizen who was captured and sold into

slavery in Ireland, but he was able to escape

and go to Britain.

In Britain,

he studied to become a priest, and when he returned

to Ireland, it was as a missionary.

NARRATOR: In March 433 CE,

Patrick travels to the Hill of Tara

hoping to convert the High King and his subjects

to Christianity.

In defiance of pagan tradition,

he lights a bonfire on the nearby Hill of Slane.

By placing his Easter fire up here,

he was making a statement about the arrival of

Christianity in opposition

to the pagan fires that were burning on the Hill of Tara.

NARRATOR: The fire enrages the High King,

who dispatches warriors to arrest St. Patrick.

Well, St. Patrick's powers of persuasion are so good,

he actually converts some of

the king's warriors to Christianity.

HUNT: St. Patrick's conversion of many of the Irish

from Tara is the advent of Christianity in Ireland.

NARRATOR: Now, the site seen from space represents

the link between pagan and Christian Ireland.

And it's also a symbol of the country's

journey from British rule to freedom and independence.

What this place tells me is how the past

shapes the present and probably also will forge the future.

NARRATOR: Coming up,

the bug that fought for America's freedom.

America might owe its very independence to this disease.

NARRATOR: And Putin's secret death squads.

There is really no oversight of this group

and what they get up to.

NARRATOR: August 2018 -- aerial surveys of

the coastline near Barnstable, Massachusetts, spot

something unusual.

We're clearly looking at what appears to be a wetland region,

but alongside these meandering waterways,

you can see these dead straight lines carved out in

perfectly symmetrical rows.

Some of them are vertical, some are horizontal.

There seems to be no rhyme

or reason to the pattern of these lines.

NARRATOR: The strange carvings stretch out across

50 miles of the semi-submerged landscape.

To have this level of construction

in a marshland region, I would assume that this must

be some sort of government initiative.

NARRATOR: Analysts use Maxar's SecureWatch technology

to scan other U.S. wetlands for clues.

This site in Louisiana has very similar-looking parallel

lines, interconnecting with more natural waterways

in the area.

We know these waterways were constructed

during World War II for the war effort.

NARRATOR: Louisiana's bayous ran slow and silent for

countless millennia.

That changes in the 1940s, when they become

a focal point of U.S. efforts to power its war machine.

One of the things we see in the Second World War

is this massive uptick in consumption of oil.

This is what's driving the jeeps

and the trucks and tanks and the planes across Europe.

NARRATOR: During World War II, the U.S. produces around

300,000 aircraft,

90,000 tanks, and two million army trucks.

To fuel them,

the military needs 100 times more gasoline

than it did during the First World War.

That increased demand for gas led oil companies to seek out

new fields, and one of the places they searched

was Louisiana.

NARRATOR: Over the course of the war,

prospectors discovered 29 oil fields in the state,

helping to increase national production by 30 percent.

These companies dug canals through the marshlands.

The idea was that this would allow transport ships to

get more easily from the source of the oil

to where it was being refined.

NARRATOR: Historical records reveal the waterways in

the Massachusetts image are indeed

the legacy of warfare,

but one waged against an enemy that

has killed many more people than the Nazis.

These lines are trenches dug as part of the battle against

the deadliest foe that America and the world has ever faced,

the mosquito.

NARRATOR: Some scientists estimate that over history,

malaria-carrying mosquitoes have killed 52 billion people,

half of all human deaths.

The disease reportedly afflicted Tutankhamun,

Alexander the Great,

and may have even contributed to

the collapse of Rome and its empire.

Back in the day,

they didn't have a very good way of dealing with malaria.

In fact, they didn't even know it was caused by mosquitoes.

They thought it was caused by bad air.

In fact, the name malaria means bad air.

KOUROUNIS: Some of the treatments ranged from

eating spiders to drinking your own urine

to draining your blood.

Needless to say,

these treatments weren't very effective.

NARRATOR: It's believed that malaria was brought

to North America by colonists

and enslaved Africans in the 17th century.

After feasting on settlers' infected blood,

it takes hold in local mosquito populations before

spreading down the east coast.

The first western settlers in America

had a terrible time with malaria.

One of the earliest towns in

the Americas had repeated outbreaks of the disease.

Over the following decades and centuries,

malaria decimates both indigenous

and settler populations...

[gunshot blasts]

...and even plays a defining role

in the War of Independence.

The American victory at the Battle of Yorktown is,

in part, attributable to the fact

that only about half of the British troops were

considered combat effective,

the rest suffering from the debilitating effects

of malaria.

America might owe its very independence to this disease.

NARRATOR: In 1897, a British scientist

makes a discovery that ultimately

leads to the strange patterns in the image.

While dissecting a mosquito,

Sir Ronald Ross identifies the malarial parasite,

the first time a link is

established between the insect and the disease.

This allowed us to suddenly have

an opportunity to control the disease.

If we could figure out a way to control the insects.

[insects buzzing]

NARRATOR: Malaria is only carried by female mosquitoes

who breed in stagnant water.

In the early 20th century,

authorities formulate an ambitious plan to eradicate

them from vast swaths of the continental U.S.

The government decided to invest in building giant

mosquito trenches in America's wetlands,

and that's what we're looking at in this image right here.

The idea was to drain stagnant water,

taking away any type of breeding environment for

the mosquitoes to procreate.

NARRATOR: To drain the stagnant water,

562,000 acres of trenches are excavated

in salt marshes along the Atlantic coast.

The laborers are one of many groups the government puts to

work on different projects to combat

soaring unemployment across the nation.

These projects involved a huge amount of manual labor,

so it was actually a great way to keep people

employed during the Great Depression.

NARRATOR: Thanks to the trenches and the use of insecticides,

malaria is all but eradicated in the U.S. within 16 years.

Today, these scars, relics of the country's 350-year war

with the disease, are still visible from space.

It's absolutely incredible to think that something as simple

as a trench could all but rid the country

of one of history's most deadly diseases.

NARRATOR: Coming up, the Saharan riddle.

OKEREKE: It looks like the sort of thing

you would see in Star Wars, not in the African sands.

NARRATOR: And the town that became a tomb.

There wouldn't even be any time to get out of your home.

NARRATOR: January 2021.

Satellites flying over North Africa

study the desert sands below.

This photo is taken way out in the middle of nowhere in

the Libyan desert, and yet here's this enormous,

mysterious structure.

OKEREKE: It almost looks like the sort of thing

you expect to see in Star Wars,

but not in the African sands.

NARRATOR: Scans of the wider area yield a possible clue.

The structure sits alongside a 43-mile-long trench

penetrating deep into the desert.

This desert is home to the pipelines for former

Libyan dictator Muammar Gaddafi's infamous

grand Man-Made River Project.

Perhaps this is part of that.

NARRATOR: The murderous dictator, Muammar Gaddafi,

rises to power in 1969,

appointing himself as the king of kings of Africa.

Gaddafi was seen as a madman and a tyrant, not just by

the international community,

but by his own people over whom he exerted

absolute control.

NARRATOR: To bolster his domestic power base,

Gaddafi sets out to solve a major problem facing

his country, a lack of water.

So when Gaddafi came to power,

it was his dream to exploit an aquifer that had been hiding

beneath Libya for millions of years.

NARRATOR: In 1983, Gaddafi launches the $25 billion

Great Man-Made River Project to

tap into the 36,000 cubic miles of water

hidden under the Libyan sands.

This project is the world's largest irrigation

project -- essentially,

it's a network of pipes pumping water out of the desert

reserve and sending it over to the big cities.

NARRATOR: Yet while pipelines do run through this region,

military experts reveal the trench and structure in

the image serve a very different purpose.

JANULIS: This image seems to have a sort of tactical makeup.

You've got areas where you could put defensive positions.

It's hard to tell, but I'd suggest

this is some form of military installation.

NARRATOR: Libya has been embroiled in conflict

since 2011, when a series of uprisings

known as the Arab Spring

engulfs the Middle East and North Africa.

In Libya, Gaddafi is overthrown and beaten to death.

His killing ends 42 years of tyranny.

But the country's troubles are far from over.

MUNOZ: Once Gaddafi died, you sort of ripped the lid

off of this Pandora's box of Libyan leaders

and exiles who are all sort of jockeying for position

of power in the country.

NARRATOR: In 2014, a disputed election

results in two rival factions

battling for control of Libya,

with each based on either side of the trench in the image.

As the country descends into chaos,

it begins to attract the attention of predatory

foreign powers.

Libya is a really attractive country

because of its massive oil reserves.

It has the largest in Africa

and the ninth largest reserves in the world.

NARRATOR: With some 48 billion barrels of oil reserves,

the Libyan sands have recently become a target for Russian

President Vladimir Putin.

Russia derives a lot of its income from oil,

and it's in their interest to control as much

of the oil supply in the world as possible.

This, frankly, makes Libya a great prize for the Kremlin.

NARRATOR: Intelligence reports suggest

Putin is using the site in the image to support

the Libyan National Army,

one of two forces vying for control of the country.

So what's important to know is that there are no Russian

government soldiers in the area,

but there is a private military group called

the Wagner Group, made up of

really highly trained Russian ex-servicemen.

Putin has a long history of using private security firms

like the Wagner Group to do his dirty work.

It enables him plausible deniability among world leaders.

NARRATOR: The Wagner Group is shrouded in secrecy,

but it's believed to employ 6,000 highly trained

Russian mercenaries.

[rapid gunfire]

It has been linked to atrocities in Syria

and tasked with assassinating Ukrainian President

Volodymyr Zelensky.

They rely on intimidation and terror

and have been known to torture and murder people.

But as a private secretive organization,

there is really no oversight of this group

and what they get up to.

NARRATOR: As well as gaining control of oil supplies,

the fear is Libya could give Putin

a base to launch attacks across the Mediterranean.

Having a military presence here allows Russia easy access

to the southern side of Europe and, for Putin,

the potential to surround his NATO rivals.

NARRATOR: What's more, Putin appears to have recently

established 30 other military installations

in Libya.

Satellites continue to play a key role in

monitoring his next move.

MORAN: The scale of these fortifications

shows just how seriously Putin takes

keeping Russia involved in Libya.

NARRATOR: Coming up, the white wall of terror.

Think of it as a steam train, completely unstoppable.

NARRATOR: And the river of gold.

This is truly precious stuff.

NARRATOR: July 2021.

In the skies over Lancaster, Pennsylvania,

aerial archaeologists using Lidar discover ghostly

structures hidden beneath the tree line.

If we look under this layer of vegetation,

what we can see is roads,

maybe remnants of buildings, like an abandoned town.

It's just super weird to me.

NARRATOR: The ghost town appears to house

the remains of over 30 buildings.

There's no immediate signs around here that tell me

why it was abandoned,

but it certainly was at some point, and the entire town was

left to nature to completely reclaim it.

NARRATOR: Analysts turn to local archives for clues.

KOUROUNIS: Looking at the historical records,

this town has a name -- Safe Harbor.

KAYS: Documents showed that this town was

part of the industry that really built Pennsylvania.

It was part of the iron industry.

NARRATOR: The town has its origins in the 19th century,

when the state's newly formed Pennsylvania Railroad Company

begins expanding at a frenzied pace.

[train whistle blows]

It's part of a national explosion in rail use,

which will see more than 200,000 miles of track

laid down in a little over five decades.

Each mile needs 50 tons of iron,

so the company builds an ironworks

and town for 250 workers on the Susquehanna River.

Obviously, you need a tremendous amount

of iron to build a railroad.

And the town of Safe Harbor

and the ironworks there were perfectly positioned

to provide that.

NARRATOR: Iron produced at Safe Harbor helps

the company form a 2,600-mile rail network

in just 15 years.

It will go on to carry 20 percent

of all passengers in the US.

The Pennsylvania Railroad Company grew so large

and so fast that it became the largest railroad

in the entire, world with over 11,000 miles worth of tracks up

and down the eastern seaboard.

Without company towns like Safe Harbor,

none of it would have been possible.

NARRATOR: As the railroad expands, so does the town,

with new schools,

beer halls, and homes built with the money

made from making iron.

But in 1861,

its residents play a role

in a very different chapter of U.S. history.

When the American Civil War broke out,

the town of Safe Harbor was perfectly positioned

to transition from making rail lines to making gun barrels

and weapons for the Union forces.

NARRATOR: The ironworks produces the newly designed

Dahlgren guns for use on the conflict's

revolutionary ironclad warships.

The money generated from making weapons means the town

escapes the economic ravages of war,

but it turns out that there are other forces

it cannot withstand.

DENNIE: In 1904, this area experienced a winter

unlike any it had ever experienced before.

Not only did the river freeze over,

but we had up to two-feet-thick ice.

NARRATOR: Production at the ironworks grinds to a halt,

as Safe Harbor's inhabitants battled temperatures of

minus 42 degrees Fahrenheit.

The subzero conditions freeze the Susquehanna upriver

from the town, creating a giant dam of ice.

Any time you block a river,

water pressure is gonna build up behind it, and the pressure

continued to increase until eventually, the ice smashed,

and the result is

an avalanche of ice and water racing downstream,

destroying anything that it hits.

There wouldn't even be any time to react.

The water is rising so quickly,

you wouldn't even be able to get out of your home.

NARRATOR: Buildings are obliterated

by the enormous chunks of ice,

leaving survivors of the floodwaters homeless.

We completely underestimate the power of moving ice

and water.

Think of it as a steam train, completely unstoppable.

NARRATOR: In just 15 minutes, the town is wiped from the map.

Over the next 100 years, its ruins are swallowed by forest,

but today, they are being revealed

once again from the skies.

KOUROUNIS: Even though the town of Safe Harbor no longer exists,

it's amazing how much history went through this little

speck that most people have never even heard of.

NARRATOR: Coming up, the Himalayas' mystery cipher.

It looks like Lego bricks pressed into the earth.

NARRATOR: May 2020.

A satellite passing over

the Himalayas spots something strange hidden

between its peaks.

DENNIE: When you look at this image,

the first thing your eye is drawn to is this river kind of

snaking through the middle.

But if you look again,

you see these unusual-looking structures.

NARDI: There seems to be hundreds,

and they're lined up along the water's edge

along the length of the river.

RODRIGUEZ McROBBIE: It almost looks like a whole bunch of

Lego bricks have been pressed into the earth.

NARRATOR: The structures sit in a remote, steep valley,

7,500 feet above sea level.

It would be very treacherous to access.

You have to wonder what's motivating people

to go down there.

NARRATOR: Analysts wonder if the color of the structures

offers a clue.

The significance of red in Tibet is sacred.

It has to do with power and authority.

So red is confined to religious architecture

and symbolism.

NARRATOR: Nearly 80 percent of the population

follows Buddhism,

a faith that reaches Tibet in the 7th century CE

and governs almost every aspect of life here.

Buddhism is the main faith in Tibet.

So it's possible that these structures are a sacred

site where Tibetans come to meditate and seek nirvana.

NARRATOR: But more detailed analysis of the aerial images

reveals the structures don't serve a spiritual purpose.

KOUROUNIS: These aren't buildings at all.

There are thousands of salt pans,

evidence of an ancient method of

salt production that's still going strong today.

NARRATOR: There are 3,000 pans along the Lancang River,

with each one producing 1,000 pounds of salt a year.

To harvest it,

locals used techniques that have been perfected for

more than 40 generations,

using briny water stored in wells along the river.

AUERBACH: The brine is collected from the wells

and then transported to these salt pans

spread out, and then the water evaporates,

leaving the salt behind.

NARRATOR: Salt's ability to preserve food

and its use in medicines and religious rituals

made it one of the most valuable commodities of antiquity.

That meant the structures in the image were a focal

point for one of the superhighways

of the ancient world, the Tea Horse Road.

HUNT: The Tea Horse Road rivals the Silk Road

in economic importance and geographic importance.

Salt was part of the wealth brought

along that, because salt was good as money.

NARRATOR: Founded in the sixth century,

this 1,500-mile route guides caravans of horses on

a perilous six-month journey through the Himalayas,

linking China to Tibet and India.

The road is one of the riskiest trade routes in

the world.

Not only did you have to negotiate high,

unscalable mountains

and the raging rivers running through the bottoms of those

steep valleys,

bandits are everywhere waiting to take your goods from you.

NARRATOR: The salt produced in Tibet

is traded in both China and India,

earning vast riches

for those who complete the dangerous journey.

Such trade routes, or salt roads, are also vital to

the success of other great civilizations,

including the Egyptians, Romans, and Phoenicians.

The trade of salt has been fundamental throughout the ages.

We've seen it traded throughout various empires

in our history.

Roman soldiers were paid in salt.

This was called a salarium.

This is also where we get our modern word, "salary."

AUERBACH: There have been periods in history where salt

has traded for nearly twice its weight in gold.

This is truly precious stuff.

NARRATOR: In more recent times, salt produced

along the Tea Horse Road

played a role in one of the defining moments of

Asian history.

So during the British occupation of India,

there was the Salt Act of 1882, and what that meant was salt

could not be bought from anyone

else but the British rulers at the time.

AUERBACH: To add insult to injury, the British levied

an extortionate salt tax,

which inflicted tremendous suffering on

the poorest of Indians.

NARRATOR: The 1882 Act also bans the production and collection of

salt in the region,

fueling the already growing bitterness between the Indian

population towards British rule.

In 1930, this simmering resentment

reaches a boiling point.

Mohandas Gandhi, before we know him as Mahatma Gandhi, was

really anti-colonial, and he decides to stage a protest.

What Mohandas Gandhi realized is that going against

the salt tax was one of the perfect ways

to break the bonds of British authority, to protest

their colonial rule, without resorting to violence.

NARRATOR: On March 12th, Gandhi gathers his followers

and walks 241 miles toward the Indian coast.

His plan is to openly defy the 1882 Act by making salt

from seawater.

Tens of thousands joined the March along the route,

sparking peaceful protests throughout the region.

And this started the ball rolling on

what culminated in Indian independence from British rule.

NARRATOR: Today, India is one of the world's

most industrialized nations and a military superpower.

Back along the winding Tea Horse Road,

these 1,000-year-old pans continue to produce

the commodity that helped

the country gain its independence,

a reminder of the incredible role salt has played in

the rise and fall of nations, visible from the skies.

HUNT: Whether as a currency or as a commodity

or as a culinary spice,

salt again and again touches upon all of human history.