Devil's Hole in Death Valley is over 500 feet (152 meters) deep, and the bottom has never been mapped.
Devil's Hole is a water-filled cavern cut into the side of a hill in the Ash Meadows National Wildlife Refuge, located in Nevada, near Death Valley National Park. It's a unique and fragile ecosystem, primarily known as the habitat of the endangered Devils Hole pupfish ( Cyprinodon diabolis). The water in Devil's Hole is geothermally heated and maintains a constant temperature of around 93 degrees Fahrenheit (34 degrees Celsius).
The extreme depth and challenging conditions within Devil's Hole make it difficult to explore and map completely. Divers have explored to depths exceeding 500 feet, but the full extent of the cavern remains unknown. This makes it one of the most mysterious and fascinating aquatic environments in the world. The isolation of the Devils Hole pupfish for 10,000 to 20,000 years makes this place of great interest to many scientists.
