Maryland's only show cave might not be the largest, but it’s packed with stunning formations at every turn. Crystal Grottoes ...

Venturing into the heart of the earth to discover the Cave of Crystals is an adventure like no other. Located in Naica, ...

Floyd Collins got trapped in a Kentucky cave 100 years ago this week, an incident that led to the creation of Mammoth Cave National Park.

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?