Into the Lost Crystal Caves
NGC goes inside one of the world's most amazing natural wonders: a huge crystal cave that's been likened to Superman's fortress, with crystals up to 36 feet long and 55 tons in weight. A group of experts go into the cavern, enduring temperatures that could kill a person in just 15 minutes. Physically, they'll go over their limits to explore a crevasse that could lead to another crystal cave, which could be even more beautiful than the first one.