All language subtitles for Life.After.People.S03E06.The.Underground.Rises.1080p.HULU.WEB-DL.AAC2.0.H.264-RAWR_track3_[eng]

What would happen

if every human being
on Earth disappeared?

No matter how we might vanish,

this is the story
of what could happen

to the world we leave behind.

Now, life after people
goes underground.

Humanity's colossal cities

stand on top of the hidden
world beneath the surface,

carved by human hands.

It's a fragile maze
of pipes and tunnels,

and when we're gone,

the world above is torn apart
by what rises from below.

5,000 miles of oil pipeline
becomes nightmare fuel,

from Baton Rouge to
Atlanta to Baltimore.

Millions of gallons
of highly flammable gas

are just rushing in
with no one to stop it.

The entire area looks
like hell on Earth.

New York
City's subway system

gets a whole new clientele.

There are rats everywhere.

They're scampering
up pipes and drains

and, yeah, toilet
lines to escape.

And 11,000
miles of underground coal

is exposed,

threatening to turn America's
heartland into a wasteland.

It's a powder keg.

All it needs now is a light.

From
sinkholes to steam pipes,

from tunnels to cavernous mines,

without people, will
our most iconic cities

be brought down by
what lies beneath?

Welcome to Earth:
population zero.

Times Square is frozen in time.

No honking horns on
the Brooklyn Bridge.

Not one pedestrian in front
of Rockefeller Center.

The city that never
sleeps has fallen silent.

But there's another world
beneath the pavement

that's still wide awake.

There are 36 subway lines

crisscrossing New York
City's five boroughs.

If you laid all of
the tracks end to end,

they would stretch from New
York all the way to Chicago.

Some of the
subway lines are automated,

run from a massive
Manhattan control room.

But the rest of the system
is well over 100 years old.

In the time of people, it was
run by nearly 300 operators,

pulling a series of levers
to change the signals

and trigger track switches.

Keeping the subway system
running is an enormous job.

The Metropolitan Transit
Authority employs 70,000 people

to make it all work.

That's like the
entire population

of Flagstaff, Arizona.

Now, there's
no one watching the traffic,

no hands on the handles, and
no one driving the trains.

Without operators, some trains
could accelerate to a point

where the automatic brakes

wouldn't have enough
time to stop a train,

and that's 400 tons of metal

moving at up to
60 miles per hour.

The part of the system
that isn't automated

is still run essentially the
way it was a century ago.

Some of the wiring is so old

that it's still covered in
cloth instead of rubber.

And with nobody
pulling the levers,

some subway cars would
end up on the wrong tracks

with other cars
coming right at them.

First few cars would
crumple like soda cans,

and that sets off this chain
reaction called telescoping,

where each car kind of slides
into the one in front of it,

and they all collapse down
almost like a telescope.

You'd have other cars that
would just fly off the tracks,

maybe smash into a tunnel wall,

or even crash into other
trains on parallel tracks.

They would almost certainly
damage the third rail

that powers all the trains.

So you'd have sparks,
you'd have fires,

maybe even explosions.

Trains carrom
into walls like battering rams,

sending fissures through walls
and ceilings like spiderwebs

and shockwaves through
the pavement above.

Now with no one
left to protect it,

the system faces its oldest,
most relentless enemy:

water.

The New York City
subway system is old.

It was opened in
October of 1904.

By 1908, tunnels were being
built under the East River

to connect Brooklyn
to Manhattan.

There are now four tunnels

that run under the
East River alone,

and it's estimated that
there's almost 60%

of the entire subway system
under the water table,

which means flooding
is a constant threat.

Leaks are so common that
crews go out every night

looking for them,

and on average, they find
30 leaks every single week.

After people,

there are no workers
to check for leaks,

no one to sound the
alarm when tunnels flood.

The only thing that stands
guard over the subway now

is a network of antiquated
pumps mankind left behind.

There are approximately
280 pump rooms,

vigorously pumping out about
14 million gallons of water

on a daily basis.

That's about 28
Olympic-sized swimming pools

worth of water every day.

Most of them have what's
called a float switch.

It's kind of like the one
that sits in your toilet tank.

It's this buoyant ball that
sits on top of the water,

and once it gets high enough,

it automatically turns
on all the pumps.

But some of the pumps
are almost 100 years old,

and they need
constant maintenance.

One by one, the
ancient pumps begin to fail.

Water seeps into tunnels
already fractured

by runaway subway cars

and begins to gnaw at
the city's foundations.

But there's something else
creeping into the tunnels.

For anyone who's
ever taken the subway,

they know it's not just people

going about their day on the
platforms; there are rats.

Once,
these vermin were locked

in a constant battle
with human exterminators.

After people, rats are poised
to rule the underworld.

But will destruction and
decay threaten their reign?

From New York, all the
way south to Florida,

and north to New Hampshire,

the buzz and whir of
electricity still pulses,

even though there's
no one left to use it.

Four million homes
east of the Mississippi

draw power from
coal-fired plants.

And the coal itself
lies hidden beneath

a huge swath of the US,
so impossibly huge,

it's bigger than nine
different individual states.

The Pittsburgh coal seam is
essentially a massive deposit

of coal in the
Appalachian Basin.

It stretches over 11,000
square miles underneath Ohio,

West Virginia,
Pennsylvania, and Maryland.

Coal provides more
than half the electricity

for the entire country.

And at least 90%
from this deposit

goes to power plants that
help keep a big chunk

of the Eastern Seaboard
up and running.

Coal doesn't
explode, it burns.

But if it did explode,

there's enough energy contained
in that Pittsburgh coal seam

that it's almost 5,000
times more powerful

than all the nuclear
weapons on Earth combined.

At the mouth
of the Pittsburgh coal seam

sits the biggest
underground mine in America:

the Bailey Coal Mine.

Its machines are now silent,

its buildings abandoned.

But 700 feet below the surface

lurks like a
slumbering leviathan

waiting to wake.

At its peak, it's producing
more than 45,000 tons of coal

every single day.

It's critical for
supplying the resources

needed for steel production

that keep the whole
country running.

In
the time of people,

hundreds of workers
traverse the mines,

relying on a complex ventilation
system to pump in fresh air

and filter out dangerous
particles of coal dust

and methane gas.

Now, there's no one
monitoring the gauges.

No canary in the coal mine
to serve as a warning.

Methane is wildly dangerous

even when proper
precautions are taken.

It's highly flammable

and can ignite at
concentrations as low as 5%.

So all you need is
a spark, and boom!

Three
days after people,

the machines are silent,

the conveyors still.

No coal is being shipped,

and power plants all over
the world are shutting down.

Coal is used to
produce electricity,

but ironically, this coal mine

is struggling to keep
its own lights on.

72 hours after
people, with one last gasp,

the mine's backup
generators run dry,

and the vast
underground coal seam

is no longer held in check.

The fans make one final
rotation before stopping.

The tunnels start
filling with methane.

The air is getting
hotter and hotter.

It's suffocating.

The entirety of
the Bailey Coal Mine

has turned into a powder keg.

All it needs now is a light.

The Bailey Mine
is just a gateway behind it,

coal lurks beneath 11,000
square miles of land.

If it ignites, the American
heartland will crumble and burn,

from Ohio to
Maryland and beyond.

New York
City's streets are silent,

but in the underground
world they were built on,

water from the surrounding
rivers is seeping in,

weakening everything it touches,

while the new rulers of the
subway system are thriving.

All of these rats
have been living it up

underneath the city streets.

They're pretty adept
at taking on the water.

Rats can swim really well.

They're able to tread
water for up to three days

and go a mile at a time.

If there's one thing
rats are good at,

it's making more rats.

They have huge litters,
they breed like crazy,

and they're sexually mature

when they're only
five weeks old.

So instead of the
three million rats

that are estimated to
be around with humans,

now there are about six million.

There are no
exterminators to bait traps.

No one to clear nests.

Once considered
the lowest vermin,

rats now rule, feasting on
scraps humanity left behind.

New Yorkers throw out

about eight million
pounds of food a day.

It is a feast for rats.

And there are so many sugars
and carbohydrates in our diet,

that's what they're
used to eating.

The rats in New York City

have actually adapted their
metabolism to our garbage.

There's something
else humanity left behind,

and it's been festering
for weeks: sewage.

Older parts of the city
have a combined sewer system,

which means rainwater and
wastewater share the same pipes.

New York City gets about
45 inches of rain per year,

which means it wouldn't
take long for those pipes

to get clogged and overwhelmed.

At that point,

raw sewage starts pouring
into the subway system.

The subways are
basically just filled

with this toxic soup.

It's water, it's sewage, it's
garbage, it's street runoff,

and it is just chock-full
of nasty stuff like E. coli.

Rats thrive
in filth and grime,

but E. coli is
deadly even for them.

So they flee the
drowning subway tunnels

for the streets above.

And without people
to keep them out,

new shortcuts have emerged.

Since the tunnels are
pretty much entirely flooded,

there's only one direction
for the rats to go: up.

They're traveling the
same route our waste goes,

except in the
opposite direction.

They're scampering
up pipes and drains

and, yeah, toilet
lines to escape.

- The rats'
reign beneath New York City

was brief, and soon
new invaders will rise.

The rodents join a new
world above the ground,

where deer roam the streets
and black bears prowl for food.

But in another part of
the underground world

beneath the city, there's
an invisible danger

growing day by day,

a vast and twisted system
of superheated steam.

Beneath the sidewalks
of New York City

lies one of the most
extensive systems

of pressurized steam
tunnels in the world.

There are over 100 miles
of pipe delivering steam

that's used to heat buildings,
power laundromats,

sterilize hospital
equipment, and much more.

The pressure of the steam

in the pipes underneath
New York City

is up to 150 pounds
per square inch.

If a valve sticks,
or a seal degrades,

or groundwater seeps in,

you don't just get a leak;
you get an eruption.

In 2007, a steam
explosion in Midtown

left a crater that was 40
feet wide and 15 feet deep.

In
the time of people,

remote monitoring systems track

the built-up pressure
inside the pipes.

Now, the pressure is
rising unchecked.

How long before they erupt,

breaching the asphalt that
divides the city above

from the underworld below?

1,600 miles from New York City,

near the Gulf Coast
in Houston, Texas,

lies the mouth of
the longest oil

and gas pipeline in the country.

A vast steel serpent buried
half a dozen feet underground.

The Colonial Pipeline
is the largest of its kind

in the United States.

It spans 5,500 miles
from Texas's Gulf Coast

through major hubs in
Georgia and South Carolina

to its terminus in
Linden, New Jersey.

Nearly 100 million
gallons of fuel

churn through the pipeline
each and every day.

Now, to put that in perspective,

it would take
10,000 tanker trucks

stretched from New
York to Chicago

to deliver the same
amount of fuel.

There are pipelines like
this all over the world,

and in fact, if you
combined all of them,

that's enough pipe to encircle
the entire Earth 30 times.

The pipeline
snakes across the country,

connecting directly to
now-abandoned major cities

like Nashville, Atlanta,
Charlotte, Washington, D.C.,

Baltimore, and Philadelphia.

After people, the flow
of fuel has stopped,

but the automated system
meant to prevent disaster

might be causing it instead.

There's an automated
system that controls valves

spaced about every 20 to
30 miles along the pipe.

If this system detects
any sort of problem

in any one section,

it will close those valves
like emergency doors.

The valves keep any
accidents or issues

within a section contained,

so it can't jeopardize the
entire 5,500-mile pipeline.

The problem is, the
system is designed

to shut all the doors in the
event of a power outage.

With grids all across
the country failing,

all the doors would be closed.

And this means that fuel will
be stuck in those sections

across all 5,000
miles of pipeline.

Even a
little bit of heat

causes fuel to expand.

In the time of people,

technicians would adjust the
valves to release pressure.

Now there's no one to
see the warning lights,

no one to man the controls.

No people means the
pressure builds and builds

to dangerous levels.

As the pressure builds
inside the pipeline,

it starts to press
against the steel,

causing it to groan
and whistle as rivets

and welds are just
struggling to hang on.

With a
sickening crunch,

the metal bursts open and the
toxic contents break free.

The connective
sections of the pipeline,

where the segments are
welded and riveted together,

are the first ones to buckle.

Vaporized gas streams out
first through the gaps,

which then allows for
the liquid gas to escape.

Liquid and vapor

work their way toward the
surface like a serpent,

poisoning the soil as they rise.

Gasoline oozes out
through cracked pavement,

pooling in the streets and
near the nests and dens

of wild creatures who have
made these cities their home.

This is exactly
the type of disaster

that people worked
so hard to avoid.

In 2020, teenagers
noticed that there was gas

bubbling up from the ground

near their home
in North Carolina.

They called 911, and it
turned out to be a gas leak,

and it took over 200 people
to complete the repair

and cleanup process.

The leak turned out to be

over a million
gallons of gasoline,

and that's with
workers dedicated

to maintenance and oversight.

Now, there
are no repair crews,

no one to clean up the spill.

All it will take is a spark
to send flames ripping

through some of the
biggest cities in America.

Six
months after people,

the biggest underground
coal mine in the country

is choking on toxic fumes
hanging heavy in the air.

Underneath it, coal
stretches across

11,000 square miles of
the American heartland.

The power and
ventilation system

has been down for
six months now,

so the mine's tunnels
are thick with fumes.

There are whole
pockets of methane

just sprinkled everywhere
throughout this mine.

The
temperature inside the mine

continues to climb, and in
addition to methane in the air,

piles of coal dust are
baking in the merciless heat.

The ventilation
system would've directed

a good deal of this coal
dust out of the mine,

but without electricity,

plenty of it will have settled
into nooks and crannies.

Coal and oxygen
are a dangerous mix.

When the coal gets exposed
to air, it oxidizes.

That is a chemical reaction
that releases heat,

and as that heat
starts to build up,

at some point the coal
can spontaneously combust.

All it would take
is a fan to cool the room,

a shovel to move the dust.

But after people, the
temperature continues to spike

until the coal dust

ignites.

With the sheer
force of the explosion

that's erupting
through the mine,

there's no question now that
the entire infrastructure

that's keeping the walls
and ceilings intact

is in dire straits.

The mine is like
a house of cards

just waiting to
collapse in on itself.

The mine at the
mouth of a massive coal deposit

is burning, wood
crackling, metal twisting.

If the coal beneath
the ground ignites,

it could burn the city
of Pittsburgh from below,

melting asphalt,
opening sinkholes,

undermining foundations,

and killing plants and
animals for hundreds of miles.

In New York City,
a plague of rats

has been spreading
through the streets.

They feast on cockroaches,
swarming in the dark,

but they also
quickly become prey.

It's estimated there are
about half a million dogs

in New York City.

A lot of these designer
dogs would have a hard time

surviving in a world
without people,

but the mixed breeds
and mutts would adapt.

At first, any loose dogs
would simply scavenge for food,

because there would be plenty
of edible food left behind.

But eventually, they
would have to hunt.

They'd go after small prey
like squirrels, birds,

and even rats.

What was once
domesticated is now wild.

Feral, ruled by instinct,

they'd return to the
natural food chain.

Over time, dogs would
get leaner and stronger.

They'd be more wary of threats.

They'd start forming packs.

Within a few years, they'd
hardly be recognizable

as the pets we have today.

They'd start behaving more
like wild dingoes and wolves.

But
beneath their paws,

in the hidden world
the city was built on,

pressurized steam pipes have
been decaying for a year.

Small leaks crawling
through joints and fittings.

Finally, without
repair or maintenance,

a section of pipe explodes.

It would send a geyser
of steam 40 stories high

and go off with the force
of 50 pounds of dynamite.

Steam, superheated
to 350 degrees,

would shoot up as high
as a Ferris wheel.

The metal grates nearby
would curl like ribbons,

and the ground would
turn into a sludge.

The damage around the
explosion would be bad,

but there would be
even more damage

that you wouldn't see at first.

The sudden pressure
drop would cause

other sections of the pipe
to overheat and rupture.

Now, you have
steam leaking underground

all across the city,

like termites slowly eating
away at the foundation

of wooden buildings.

All
across New York,

geysers of steam tear holes
in the city's concrete flesh.

The wounds on the
surface are deep,

but inside the flooded subway
tunnels beneath the ground,

the wounds are deeper, and
a new invasion is beginning.

When the floodwaters
rolled in and kept coming,

that left the door wide open
for something else to move in:

catfish.

The Hudson and East Rivers

are home to some seriously
tough catfish species,

like the brown bullhead
and the channel catfish.

Now the subways would
be a full-on aquarium,

at least for catfish.

I mean, the water's
still really gross.

It's not a great place
for most animals,

but catfish do just
fine in polluted water.

So they're thriving.

They've got great
eyesight for murky water,

and those whisker-like
barbels around their mouths

are basically like
built-in sensors

to help them find their
way to food in the dark.

Here's the problem:
catfish love to burrow.

They dig into mud or
soft banks to hide out

or lay their eggs, and all
that digging is eating away

at what little is left
of the tunnel walls.

The tunnels
are already crumbling,

and now catfish burrow
into cracks and crevices,

speeding the rate of decay.

What will happen
to the city above

when the world below
rots away and crumbles?

15
years after people,

Pittsburgh, Pennsylvania, is
swallowed up by vegetation.

Black bears now prowl
the Strip District,

where shoppers once strolled.

But in the underworld
beneath the city's streets,

the biggest coal deposit in
the Appalachian Basin slumbers

as the nearby Bailey
Coal Mine smolders.

The mine's been rocked by
one explosion after another.

Methane gas, coal dust,

just lighting up like
ticking time bombs.

The place has been
getting hammered nonstop.

Sections have already caved in,

and whatever's left
is barely hanging on.

What's
left of the mine

is the last fragile barrier
protecting the shining cities

built on top of 11,000
square miles of hidden coal.

And there's no need to
imagine what could happen.

Just look at the
other side of the world.

In Australia, there's a place
called Burning Mountain,

where there has been a
coal seam fire smoldering

for more than 6,000 years.

That's older than the pyramids.

Even closer
to the Bailey Mine,

the town of Centralia,
Pennsylvania, stands abandoned,

its residents forced to flee

long before the age
of mankind ended.

Back in 1962, a coal seam
fire ignited under the streets,

probably because of
hot ash being dumped

into an old strip mine.

At first, people stayed,

even though the air was
getting thick with sulfur

and carbon monoxide.

But in 1981, the
ground gave way.

It swallowed a whole backyard

and almost took a
young boy with it.

And that was the last straw.

Despite every effort, the
fire couldn't be stopped.

By 1992, Centralia
was condemned,

left to smolder, abandoned.

Today, the fire spans
35 football fields,

and it could keep burning
for another 200 years.

But here's the kicker:

Centralia's coal seam is
about six square miles.

The Pittsburgh coal
seam is over 11,000.

This isn't a match
versus a bonfire.

This is a match versus
almost 2,000 bonfires.

With a mighty roar,

a new explosion rocks the mine,

and what's left of
Pittsburgh's skyline shudders.

The tunnels start collapsing
anywhere and everywhere,

swallowing up
everything above them.

The sound
is a death knell,

announcing the
beginning of the end.

In New York City,

the streets have been torn
open by geysers of steam,

and the foundations beneath
them have been eroded by water,

rust, and gnawing catfish.

Finally, with a low rumble,
the inevitable comes.

After 20 years of
saltwater corrosion,

even the toughest parts
of the subway system

have had enough.

With those tunnels gone,
the ground gives out,

creating gaping sinkholes

and depressions
all over Manhattan.

Like something
out of a nightmare,

whole sections of the
city are swallowed up

by the void beneath,

starting with the block above

the Rector Street
subway station.

Rector Street, like a
lot of the old stations,

was built the old-fashioned way.

It's a technique
called cut and cover.

Dig a big trench right through
the center of the street,

build the tunnel, slap the
street right back on top.

It was fast, it worked,

but those tunnels sit
just below the surface

without the solid
bedrock protection

that the deeper lines have.

And now, after decades of
neglect and flood after flood,

the weight of the city
above is just too much.

By now, every subway tunnel
in Manhattan has collapsed.

But what this means
is that everything

on top of those tunnels
is going to collapse too.

Neighborhoods reduced to rubble,

iconic structures destroyed.

Trinity
Church is consumed whole,

the New York Stock Exchange
is gone in an instant,

and the Charging Bull, once
an icon of human commerce,

disappears into the earth below.

While much of the city
is being sucked under,

there's one historic tower
still standing on solid ground:

the Empire State Building.

Now, there are some
structures that go above

and beyond building codes.

They are built to
withstand whatever

Mother Nature might
throw at them.

And this icon has
a key advantage

in a life after people.

There's no subway tunnel
directly beneath it.

That helps buy some time,

even as the city
around it crumbles.

The Empire State Building,

it will remain a symbol
of American civilization

and New York City
long after we're gone.

For now, the
iconic tower watches over a city

brought down by the
underworld beneath it.

How long can she
avoid the same fate?

Across the country, over 5,000
miles of imperial pipeline

have been slowly leaking.

Fuel now standing
in incendiary pools

in abandoned cities like
Charlotte, North Carolina.

Now, a thunderstorm is swirling
over Charlotte Motor Speedway,

and with thunder
comes lightning.

With the ground
soaked with fuel

and the air thick
with gas vapor,

the whole place goes
up in a firestorm.

Fires erupt
along parts of the pipeline

from Houston to Philadelphia.

And in Linden, New Jersey,

tens of millions of gallons
of gasoline wait in storage,

enough to wipe an entire city

off the map.

Linden, New
Jersey is the last stop

of the 5,500-mile
Colonial Pipeline.

It was once filled with
the hustle and bustle

of hundreds of workers,
but 20 years after people,

the facility now sits silent,

like a rusting ghost
town frozen in time.

At its peak, this
system stored fuels

in 37 separate tanks
waiting for transport.

Each tank can hold about
four million gallons.

Over 100
million gallons of fuel

sit across the water from
New York's Staten Island,

and only miles from
downtown Newark.

This entire facility
and the land it sits on

is essentially one giant
fuse waiting for a spark.

Leaked
fuel has charred cities

from Houston to
Baltimore, and now

holding tanks burst into
flames, releasing vapor clouds.

And they don't burn,

they explode.

Remember, one
gallon of gasoline

has the same amount of energy
as 14 sticks of dynamite.

So multiply that by four
million gallons of gasoline.

That's not a small explosion,

that's the size of
a nuclear bomb.

Within an hour or two,

everything flammable
would be gone.

Now, the walls might
still be standing,

but they would be charred,
cracked, severely weakened.

Everything within
a one-mile radius is leveled,

and shockwaves
travel over 40 miles,

shattering windows as far
away as Lower Manhattan.

The Colonial
Pipeline's spent husk

is entombed beneath
the ground forever,

but its legacy has reshaped
major cities across the country,

leaving behind charred
ruins and scarred rubble.

In Pennsylvania, years
of fires and explosions

have wiped the biggest
underground mine in the US

off the map,

and opened the
door to a disaster

of unparalleled magnitude.

Years after explosions
rocked the Bailey Coal Mine,

the earth above gave way,

flooding tunnels and
creating a massive sinkhole.

That sinkhole did more
than just swallow land;

it also exposed that
coal seam to the air.

Coal is a highly
reactive product,

and when mixed with air,

it can create these highly
flammable conditions.

Once safely
hidden beneath the ground,

coal is now alight, and these
fires can burn for centuries.

The streets of Pittsburgh
blister and buckle,

and Point State Park
is swallowed whole,

followed by the Frick and
the Cathedral of Learning.

At this point,
western Pennsylvania

isn't just falling apart;

it's becoming a
literal hell on Earth.

Fires are raging
deep underground,

and even if there were
people still around,

there's nothing they
could do to stop it.

Hundreds of miles
away, 100 years after people,

New York City has
completely transformed

from a tourist mecca
to an open waterway.

Over the decades,

all those old cut-and-cover
subway tunnels,

which were dug shallow under
the streets, have caved in.

Rainwater and groundwater
have rushed in,

filling the sunken streets.

So now, crisscrossing Manhattan,

you've got actual
flowing streams.

Back when people
were still around,

Canal Street was one
of the busiest roads

in Lower Manhattan.

It was where you went to
shop, visit Chinatown,

and hustle your way through
a sea of taxis and crowds.

There was a real canal here
once, back in the early 1800s.

It got paved over
as the city grew,

but a century without humans,
the ground has given out,

water filled in, and Canal
Street is a canal once again.

But the water
continues to eat away

at the underground world
the city was built on,

until finally, a piece of
history collapses into it,

and the curtains fall

on the legendary
Radio City Music Hall.

It took centuries,

but even giants like
the Chrysler Building

and 30 Rock finally gave in.

For centuries,

the hidden world beneath
Manhattan has been rotting,

bringing the city
down from below.

But despite the destruction,

perhaps the most iconic symbol
of New York still stands:

the Empire State Building.

Of all the city's legends,

it's no surprise the
Empire State Building

is the last to hold its ground.

Built in the 1930s with
60,000 tons of steel,

that's more than half the weight

of America's largest
aircraft carrier,

the USS Gerald R. Ford,

plus millions of bricks and
hundreds of tons of aluminum.

And that's just the materials.

Its foundation digs 55 feet
deep into Manhattan's bedrock.

It was absolutely built to last.

The decay
has been spreading

under city streets
for 250 years.

And finally, the
ground under part

of the Empire State
Building begins to crumble.

Flooded tunnels nearby,
slowly eating away at the soil,

have turned the earth beneath
it into Swiss cheese.

The northwest corner near
the old Herald Square,

which was once home
to eight subway lines,

starts to give way.

The
mighty tower falls,

crumbling into the void below,

and the once signature feature
of New York's skyline

disappears.

One of humanity's greatest
achievements below ground,

the New York City subway,

just brought down one of
humanity's greatest achievements

above ground.

Now, the
rubble that was once

the Empire State Building
acts like a natural filter,

restoring nature where the
concrete jungle once stood.

Sediment builds up,
soaking up the chemicals

and pollution like a sponge.

Bacteria moves in, helping
to break everything down.

And now, for the first
time in centuries,

clean running water
cuts through Manhattan.

The
Upper East Side,

once home to the
wealthiest New Yorkers,

is now rich with new residents.

And it's not just
the catfish anymore.

It's all sorts of wildlife
that call Manhattan home.

Where once you had tourists
walking down Fifth Avenue

and having brunch in the West
Village, now you have turtles,

beavers, and bobcats
looking for their next meal.

New York changed after
humans disappeared,

and so did the rats.

With so much of the
city now under water,

rats adapted to survive.

They could have evolved webbed
feet for faster swimming,

or waterproof fur to stay warm,

or stronger legs and claws
to be able to leap to safety

away from new
predators like bobcats.

The Big
Apple has succumbed

to the hidden world
beneath its streets.

And 250 years after people,

the Bailey Coal Mine
is all but gone,

but its fiery legacy remains.

The tunnels are long gone,
having been blown apart

by methane explosions
centuries earlier.

What remains is
the coal seam fire,

a glowing ember
across the landscape

that's been burning
for centuries,

and it could keep burning
for thousands more.

But even here, where
the ground still steams

and the air smells
faintly of coal ash,

nature is creeping back.

Along the former
path of the Colonial Pipeline,

nature also returns.

250 years later, the forest
has reclaimed the land.

But if you were to squint,

you might still be
able to make out

the contours of this imprint
of man on the landscape,

but that is all that
remains of man: a trace.

You might catch a
faint whiff of gasoline

if the wind is just right,

but otherwise, you
might never know

what was once buried there.

The story of humanity
is almost always about

controlling our environment,
shaping it to fit our needs.

This means not just
what we see in front of us

when we walk out the front door,

but all the things
that are out of sight

beneath our feet, too.

And it's amazing to think
how relatively quickly

all those things we
built beneath the surface

may be what leads to the demise
of what we built above it,

when we're no longer here to
keep it all on solid ground.