One of the largest wooden constructions in Europe was meant to be a casino, but soon became an orphanage.

Enigmatic tombs and cave dwellings on the outskirts of a rural village.

The ruins of a megalithic monument sit right in the garden of a luxurious Maltese resort.

A centuries-old forgotten underworld lies beneath Malta.

This former insane asylum now holds a pathological anatomy museum.

The dome-shaped reservoir of this old water tower produces unique acoustic effects.

A statue honors the local legend that the devil helped build St. Mary's church after being tricked into thinking it was going to be a wine bar.

An abandoned mine now resembles a post-apocalyptic landscape of derelict buildings and blood-red pools of water.

Where Aleister Crowley taught magick in "La Chambre Des Cauchemars," his "Chamber of Nightmares."

A Spanish town built into the cliffs.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

A once-luxurious, now abandoned hotel in the Italian Alps.

This century-old ruined temple was reborn as "The Church of Skate."

Haunted tuberculosis hospital built by the patients.

A Franco-era dam flooded (almost) everyone out of this centuries-old Aragonese town.

An impressive home made of stone, carved more than a century ago.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

An outsider folly near Madrid.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

Stuck in the middle of a modern Madrid city block are the remains of a 19th century sports complex.

Mysterious Spanish catacombs of unknown origins.

A huge cathedral single-handedly constructed by one eccentric monk.