Why it's incredible: The cave is so deep, the world's tallest building could fit inside it. The Hranice Abyss — or "Hranická propast," in Czech — is the deepest known freshwater cave in the ...

Polish explorers check a footage from a remote-operated vehicle deep in the Czech Republic's deepest cave. AP Photo/ Marcin Jamkowski The deepest freshwater cave on Earth, the Hranice Abyss ...

Bermuda's Walsingham cave system harbors a wide diversity of cave-dwelling animals not found anywhere else in the world. Now, ...

Cave diver Tim Senkevitch punches through a ... in the densest concentration of freshwater springs in the world. The best known are 33 "first magnitude springs," each of which produces almost ...

Some species of copepods found in mixed sea and freshwater caves (anchialine caves) are unusually primitive and provide clues as to how copepods began their invasion of the oceans. We have collected ...

The freshwater lens acts as a lid ... Even more than high-altitude mountaineers, cave divers work under tremendous time pressure. When something goes wrong, if they don't solve the problem ...

Freshwater pufferfish ... and sea urchins. They then rest in caves or crevices at night Spiky pufferfish prefer a nocturnal schedule. They hunt at night, using the hard plates in their mouth ...

The Miami cave crayfish is a relatively small, freshwater, subterranean crayfish that is found only in large holes, cavities and caves along the Atlantic Coastal Ridge. It is an opportunistic omnivore ...

With underwater caves and sapphire waters ... Wakulla Springs is one of the largest and deepest freshwater springs in the world. Adding to the enchantment of this spot is the fact that the ...