Austrian and Germans who died on British soil during World War I and II are buried here.

Surprisingly aquamarine waters fill deep lakes formed at the end of the last ice age.

The inspiration for H.P. Lovecraft's horror stories and Batman's Arkham Asylum is now a condominium complex.

This abandoned psychiatric hospital once housed more than 4,000 patients in the middle of a quaint New England town.

World's first "penitentiary," meant to be humane, drove men insane.

An abandoned asylum where patients have been forgotten but their possessions remain.

A hospital closed seemingly in the middle of operations, leaving behind fodder for horror films and ghost hunters.

An FDR-era tuberculosis sanatorium has stood abandoned in the suburbs of the U.S. capital for over 30 years.

These disused steel furnaces are now haunting ruins that may one day be a national park.

This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

One of the largest-ever mental hospitals now sits abandoned, surrounded by 25,000 unmarked graves.

Yugoslavia's biggest underground airport lies in ruins.

Underground hospital complex constructed by slave laborers during the German occupation of the Channel Islands.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

The fishing boats that moor in this small lagoon enter and leave through a tunnel to the sea.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

A spectacular cave and a beguiling lake.

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.

A Bronze age settlement on the Greek island of Santorini might have been the inspiration for Plato's Atlantis.

A quirky bookstore hidden beneath a sea of whitewashed Greek villas.

This abandoned Greek island was the last active leper colony in Europe.