A large underwater labyrinth in Florida called The Eagle’s Nest, known by some as the Mount Everest of cave diving, claimed the lives of two divers on Sunday.

The underwater cave system is deadly and only recommended for the extremely advanced in cave diving.

The Eagle’s Nest, also known as the Lost Sink, took lives of Patrick Peacock and Chris Rittenmeyer. The two men were experienced divers who had both dived in the Eagle’s Nest several times before.

Video of diving The Eagle’s Nest

After the two divers failed to meet up with a third diver a rescue crew was called in to locate the missing men. A second group of rescue divers entered the water at 9 a.m. Monday and found them near each other in 260 feet of water.

The divers were found in a very dangerous and complex area of the cave system.

Since 1981, 10 deaths have been reported in the Eagle’s Nest.