The singular ruins of a mysterious lost city.

A single column facing the sea is all that's left of one of the most important temples of Magna Graecia.

Some claim these desert ruins are from the legendary "Atlantis of the Sands."

The once great capital of Egypt now crumbles forward as evocative ruins.

China's very own Atlantis is an ornate dynastic city resting at the bottom of a lake.

An ancient city exhumed from the depths of the ocean.

Abandoned Soviet base once stocked with short and medium range missiles pointed at western Europe.

The ruins of an Estonian prison are drowning in the quarry lake where the convicts were once forced to work.

A gallery of underwater art that can be visited by man and fish alike.

A community of collapsing homes more than a mile out from the Florida coast.

An underwater city for the dead.

One of the deepest blue holes in the world.

A natural swimming hole that was once a ceremonial center for Mayan priests.

These enigmatic ruins continue to vex archaeologists.

An important Mayan religious and trading center dating back to 200 BC.

A massive underwater sinkhole made famous by Jacques Cousteau.

Stay in a room with a view... of the bottom of the ocean.

An underwater restaurant, surrounded by a coral reef.

One of America’s oldest and spookiest hotels, thanks to the residency of ghosts, dead presidents, and Alfred Hitchcock.

This luxury hotel suite is located deep in the bowels of an old mine.

A floating underwater hotel, created by a Swedish artist.

A unique seaside cave where Aleister Crowley faked his own death.

Enchanting cave with a river crashing through the roof.

Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.