Crystal Cavern

JORGE GUERRERO/AFP/GETTY IMAGES

WORTH THE WAIT: This crystal cave began to form 6 million years ago.

JIM MCMAHON/MAPMAN ®

 

Visitors to southern Spain can now step inside an otherworldly rock formation. A giant geode recently opened to the public near the town of Pulpí. It’s one of the largest crystal-filled rocks ever discovered.

The geode began forming millions of years ago as mineral-rich water seeped underground. The water slowly evaporated, changing from a liquid to a gas, leaving behind crystalized minerals. Over time, the crystals gradually grew. Some now are 2 meters (7 feet) long.

To enter the geode, people squeeze through a small opening at one end. “The first time I stepped inside, my heart raced because I was seeing something incredible,” says Javier García Guinea, a geologist at the National Museum of Natural Sciences in Madrid, Spain.

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