A Look at the Dark and Mysterious Side of Mexico

Deep in a mine in Chihuahua lies the Cave of Crystals, home to the largest crystals ever discovered—some over 30 feet long. The cavern looks like something from a fantasy world, glittering with giant selenite beams formed over hundreds of thousands of years in perfect conditions.

But the cave is dangerously hot and humid, reaching up to 150°F with nearly 100% humidity. Without protective suits, a person could die within minutes from heatstroke. Scientists could only explore it for short periods, making it one of the most breathtaking yet inhospitable places on Earth.