There are places on this planet that live sort of at the edge between the real and the unreal.

Places so extreme that it's hard to square them with any normal life.

The center of a 600 foot wide tornado whipping across the Oklahoma plains.

A lava lake bubbling with newly formed magma.

Or, for example, a 600,000 year old cave bursting with crystals, the size of a school bus.

And it looks like Superman's fortress of solitude.

There are these white, selenite crystals that crystallize gypsum.

And they are the size of tree trunks.

Some of them are 10 meters, 30 feet long, weighing 55 tons.

They look like gigantic tree trunks.

And it looked like this magical alien place.

I'm Dylan Thoris, and this is Atlas Obscura, a celebration of the world's strange, incredible, and wondrous places.

Today, we're headed deep underground to the cave of the crystals, located nearly a thousand feet beneath Northern Mexico.

And we'll meet a professional adventurer who spends his time chasing the edge of the unreal.

Do you want to just list a few places that you've traveled in your line of work?

Oh, geez.

Sure.

I'm the very first person to have ever descended down into the Darbaza Flaming Crater, the Gates of Hell.

I did the world's first ever rope traverse over top of the boiling lake in Dominica.

Chase the world's largest tornado, 2.6 miles wide.

That was in Oklahoma.

I was in the middle of Hurricane Sandy, Hurricane Katrina, all over the place, basically.

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