In January 2006 Speleoresearch & Films and the Team la Venta started a three year exploration campain to discover the Naica cave, Chihuahua, Messico.

The Cave of Crystals in Chihuahua, Mexico, is buried almost 1,000 feet (300 meters) beneath Earth's surface and contains giant gypsum crystal beams that are up to 37 feet (11 m) long.

Crystal Cave in Sequoia and Kings Canyon National Parks, CA will be closed in 2022 because of road damage from fires, Sequoia Parks Conservancy announced.

Crystal Cave in Sequoia National Park, California, reopens for the season, offering guided tours and a magical underground experience after a 4-year closure.

There are still pools underneath and underground pools, there's underground streams, and we even have a giant cephalopod fossil that can be found in the ceiling of the cave," Klimczak says.

Giant crystals that can reach sizes larger than houses grow at incredibly slow rates, taking as long as a million years to reach more than two stories tall, scientists now find.

NGC goes inside one of the greatest natural marvels on the planet - a giant crystal cave described as Superman's fortress, with magnificent crystals up to 36 feet long and weighing 55 tons. A team ...

Deep in central Vietnam a giant cave hides an ancient "world" beneath its surface, home to an entire ecosystem.