3,000 market stands in five former Zeppelin hangars.

This old Estonian mine has been kept like a sprawling time capsule of the local shale industry.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

Hidden in a secluded Greek cove is a pristine beach marred only by the rusting smuggler's hulk stranded on its shores.

This domed temple was built in a hidden cave mouth as a refuge for sinners seeking absolution.

This secret Swiss fortress is disguised as a harmless pink house, complete with fake windows.

This incredible stone temple is a monument to death, victory, and fantasy architecture.

This proud Teutonic warrior rises out of a German forest heralding a victory and measuring lightning.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

This Belgian theme park began as a refuge for bored church children and was closed down when a boy lost an arm.

Longest fortress system anywhere in Europe.

Abandoned medieval hill town.

Abandoned Nazi train station turned underground astroparticle laboratory.

At the foot of a waterfall lies a peaceful swimming lagoon and evidence of over 60,000 years of human habitation.

Spanning the El Chorro gorge, this pathway used to be one of the most dangerous crossings in the world.

This chest hospital with a dark, haunted past serves as a fitting set for horror films and a paradise for ghost hunters.

Lava stone structures possibly dating back to the 19th century may have been a stopping point for voyagers between ancient Egypt and the Mayan Civilization.

A bridge destroyed three times: once as a ruse, then in an actual attack, and finally for the movies.

A submerged village appears when dam levels drop.

The industrial monstrosity known as Bagger 258 is a colossal mining machine built in the DDR - but now left for dead in a German field.

A Netherlands hotel where you can sleep inside a wine barrel.

A fortress built to pacify local uprising that had a stint as a Nazi concentration camp before becoming a five-star hotel.

A floating underwater hotel, created by a Swedish artist.

Rent out a glass igloo to watch the Northern Lights like you live in the future.