This historical Netherlands fortress still bears the marks of its single siege.

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

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

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

Erotic art covers the walls of the largest ancient pleasure palace.

Pompeii's less famous neighbor is still revealing her secrets.

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

This entire town moved to a safe location after it was devastated by an earthquake, but the remains of the original town are still around.

Thousands of well-dressed mummies below a monastery.

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

This 16th-century monastery has been turned into a surrealist architecture compound.

1513 Turkish world map, full of European state secrets and snarky commentary.

Oldest Museum of the Netherlands is a true cabinet of curiosities.

An extensive collection of reliquaries containing the bones of saints housed in the largest Catholic church in Venice.

A modest museum in the final home of Italian poet and father of modern Italian, Francesco Petrarca.

This impressive collection of rare books on ancient mysticism inspired author Dan Brown.

This still-celebrated home was a radical architectural experiment in 3D De Stijl.

The soulless eyes of 82 bronze children stare on forever in remembrance of a horrifying World War II massacre.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Monument to a suicide protesting the Soviet invasion.

The 1936 Summer Olympics site is a crumbling remnant of sportsmanship and a history its host country would like to forget.

A slice of central Asia in the middle of Berlin.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.