Into the Lost Crystal Caves (2010) is a Documentary film that follows 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 of experts venture into the cavern, enduring scorching-hot temperatures that could kill a human after just 15 minutes of exposure. They'll push the boundaries of physical limitation to explore a crevasse that could lead to another - and perhaps more spectacular - crystal cave. Into the Lost Crystal Caves is not currently listed with streaming providers in your selected region, but availability can change over time. It has a user rating of 6.0 out of 10 from 2 votes. Fans of documentary movies may also want to explore similar titles below.