The slow-moving ride passes beneath sculpted ceilings and glowing formations ... it’s worth the stop. Crystal Cave is made of marble, not limestone, so the formations look smooth and glossy.

The stalactites and stalagmites of Sequoia National Park’s Crystal Cave, a sprawling subterranean wonder that’s been closed ...

Imagine swimming in crystal-clear waters ... Visitors can take small boats into the cave and experience its glowing waters ...

Discovered in 1999 inside an abandoned mine in Southern Spain, Pulpí Geode is the largest crystal 'cave' of its kind in the world. But what exactly is a geode and how do crystals form inside them?

If you’ve ever been on a cave tour where the guide shines a black light, you’ve seen the walls and formations glow. The stunning fluorescence is often the result of impurities trapped in ...

Crystal Cave, the ancient marble cavern at the end of a steep half-mile hike in Sequoia National Park, is slated to reopen to visitors this summer after four years of closure.The cave features a ...

The stalactites and stalagmites of Sequoia National Park’s Crystal Cave, a sprawling subterranean wonder that’s been closed for four years, will be accessible again this summer. But to get in ...