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?

As we navigate the maze-like passages, we stumble upon a hidden cave deep within the mine, leading us into an incredible underground world. With ropes guiding the way, we descend into crystal ...

Naica’s Crystals Cave, maybe the most amazing underground wonder on Earth, was discovered by chance inside the deep mine of Naica, in the State of Chihuahua, Mexico. It is a true geode: a cave ...

The cave system reopens on May 23. Visit the Sequoia Parks Conservancy website to get tickets for the tour. You can visit from May 23 through September 7, 2025. The tour times are between 9am and 3pm.

The cave is one of about 275 known caves in Sequoia and neighboring Kings Canyon National Park. The park’s only publicly ...

Fisher says a person can stay inside the cave for only six to ten minutes before ... This calcium, in turn, combined with the sulfur to form crystals on a scale never before seen by humans.

"Furthermore, it provides this unique stone, which contains a set of graphic representations of human origin that could be 100,000 years older than the oldest cave art depictions," it continued.

Visitors will be able to enjoy a half-mile loop through the narrow passages and steep sections of the stunning marble cavern ...