mankind has ever dug.

It's a straight drop

into the bowels of the Earth.

For 20 years, Russian scientists

and engineers drilled deeper and deeper,

hoping to uncover whatever mysteries

the hole may hold,

earning it the ominous nickname of

What would happen if

for whatever reason

you fell into this hole?

So, you managed to take the plunge.

You'll start plummeting at almost 10 m/sec (33 ft/sec),

and every second after that,

it gets faster.

If we take terminal velocity out of the mix,

and assume you weigh 80 kg (176 lbs),

you'd eventually reach a speed of 490 m/s (1,608 ft/s).

So as you fall deeper and deeper,

Falling at such a high speed,

you'll start to notice things getting

a little toasty

as your heart rate starts to elevate,

and panic sets in.

You might find it getting

a little harder to breathe.

Why?

At 150 m (492 ft) down,

your poor lungs would be getting crushed

by the constantly increasing air pressure.

You might also encounter what

cave explorers like to call “foul air.”

Deadly underground pockets

of carbon dioxide.

Things can't get much worse,

can they?

Yeah, they can.

Less than 3 km (2 mi.) into the trip,

you're going to see your skin start to burn up.

Literally.

And as you continue to fall,

it only gets hotter and hotter.

This is because you're being pulled closer

to the gravitational center of Earth,

and its molten core,

which is baking the planet

from the inside out.

A temperature of 80°C (176°F)

can severely burn a person's skin

in less than a second.

At this point in the hole,

you're feeling heat of over 180°C (356°F).

On the bright side,

you've probably already passed out.

When you fall out of a plane

you can pass out from lack of air,

but wake up as oxygen becomes

more available,

and catch a glimpse of the ground

just as you smack into it.

Down here, you're not waking up.

Okay, so things don't look good.

But, let's say you came prepared

and wore an atmospheric diving suit

to help with the increasing pressure as you fell.

It's heavy,

but it will help with that breathing problem.

In 2016, Luke Aikens jumped

from 7,620 m (25,000 ft)

without a parachute,

and survived without a scratch.

Granted, he landed in a net.

If he's allowed to have one, you can too.

So you land in the net. Great!

Including your terminal velocity,

you have successfully managed to free fall

12 km (7.5 mi.) straight down

at a speed of 200 km/h (124 mph).

How long were you falling?

Well, factoring in air resitance

and terminal velocity,

the whole trip took just over three minutes.

And now you've got to get back out.

This is not going to be easy.

But it may not be impossible.

In 2018, Alex Honnold managed

to scale Yosemite National Park's

914-meter-tall (3,000 feet) El Capitan granite wall,

without ropes,

in just four hours.

Granted, he wasn't wearing

a huge suit like you are.

This big outfit wouldn't help you climb.

And you would need some climbing equipment,

to help you get a better grip

on the walls of the hole.

To answer that, let's flashback to 1971,

in the Kola Peninsula of northwest Russia,

to be exact.

When Russia began work on

the Kola Superdeep Borehole.

Measuring in at just over 12 km (7.5 mi) deep,

the Kola Superdeep Borehole is

the deepest hole humankind has

managed to dig on Earth.

Team Kola had managed

to break the world record for drilling depth,

trying to get a leg up on the U.S.

during the Cold War.

Eventually, they encountered temperatures

of 180 degrees (356°F,)

which melted their equipment.

So the hole was capped in 1992.

When you're at the bottom,

you'd find things are warm, to say the least,

not to mention your body would be

dealing with air pressure equal to

54 elephants perched on top of your head,

weighing in at a whooping 378 tons!

Talk about a headache.

At least you could admire some of

the 2.7 billion year old rocks down there.

But really, could something like this,

falling down this hole, ever happen?

Who knows?

To be honest, we're still trying to figure out

the equipment requirements

for digging this deep,

let alone finding someone crazy enough

to take the plunge.

Luckily, the Kola Superdeep Borehole

only has a diameter of 23 cm (9 in.)

so it's too narrow for you to trip into.

Even with it's record breaking depth,

the Kola Superdeep Borehole is only

a fraction of the thickness of the Earth's crust.

But it does makes you think

about what humans are capable of.

Could we maybe

dig tunnels between continents?