38 Places Where Nature Looks Straight Out of a Sci-Fi Movie

20. The Cave of Giant Crystals – Mexico’s Real-Life Fortress of Solitude

Superman’s Fortress of Solitude might be fictional, but Naica Mine’s Cave of Crystals in Mexico is very, very real. Hidden nearly 1,000 feet below the Earth’s surface, this cave contains the largest natural crystals ever discovered, some reaching up to 36 feet long and weighing over 50 tons. These colossal, sword-like selenite crystals formed over thousands of years in the cave’s intense heat and humidity, creating an underground world that looks straight out of a science fiction adventure film. The extreme conditions inside (temperatures exceed 120°F) mean only researchers wearing special cooling suits can explore this jaw-dropping crystal kingdom. It’s a shimmering, alien world trapped beneath our feet—a true natural wonder that seems like it belongs in another galaxy.