Caving or spulunking is not an activity for the faint-hearted. A term used for exploring the extremes

of cave systems, the deeper you go, the less light space and even breathable air there is.

Sounds like my worst nightmare. But imagine squeezing yourself over jagged rocks and

through impossibly tight spaces in the pitch black,

when all of a sudden you come across a cave lined with crystals.

Lots of crystals.

Sparkling structures stretching from the cave's floor to its ceiling,

with some as long as a school bus.

But as mesmerizing as this place might look,

you wouldn't have long to marvel at its impossible beauty.

Well, if you want to make it out alive, that is.

Why?

Well, get your hard hat and walking boots on

as we uncover what makes this giant crystal cave

one of the most deadly natural phenomenon in the world,

and explore some other caverns that, despite their splendor, you should never step foot in.

You're listening.

You're listening to be amazed.

Whether it's their supposed healing powers or the way they sparkle in the light,

we humans have been obsessed with crystals

for as long as we can remember.

So back in 1910, when miners from Nica, Mexico discovered a

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