The Fortress of Solitude?

Didn’t I see this in a movie somewhere?

Actually, despite the similarity to the arctic Fortress of Solitude in the “Superman” movies, this is a real cave in Mexico. The Cueva de los Cristales has some of the world’s largest known natural crystals — some of them as long as 36 feet. No, it’s definitely not ice. They’re gypsum crystals, formed over a few thousand years, thanks to mineral-rich water that used to fill the caverns and a constant temperature of 136 degrees.

Hopefully, they can figure out some way to preserve the cave — it’s in some danger from local mining, and it would be nice to see something that beautiful preserved.

(Link via Oliver Willis)