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

A lake with hundreds of ancient skeletons surrounding it. The surprise is what killed them.

An ancient monastery, a locked room, and a mysterious book heist.

The oldest Jewish cemetery in Europe survived Hitler's Germany.

"Alleys of Stone" form natural mazes in Spanish natural park.

The world's most famous cheese caves.

Green labyrinth formed by a karstic maze hidden in a preserved oak forest.

Of course Salvador Dalí lived in a castle...

A darkly erotic open-air statuary in Catalonia.

Wonderland replication in progress by one persistent man.

A breathtaking canyon offers stunning views and frightful pathways through an ecological paradise.

An isolated village literally built into the crevices and rock formations of a mountain.

18th century anatomical amphitheater of the Royal College of Surgery of Barcelona.

The world's largest drain sits below the city of Kasukabe, Japan.

This whimsical winery by Antoni Gaudí looks ripped from the pages of a fairytale.

Week-long block party becomes a competition for the best decorated street.

Holy Grotto of Montserrat Monastery holds one of Europe's mysterious black Madonnas.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

Countless stories attempt to explain Poland's mysterious J-shaped trees.