Original subtitles

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.