Centuries-old bridges grown from tangled roots.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

A submerged archeological park still holds the wonders of a Roman Sodom.

A 16th-century horror show built in a lovely Italian garden.

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

Giant marble phalluses on the sacred island of antiquity.

Replicas of Apollo's leonine stone guard cats still line a sacred row in Greece.

The oldest hall in Iceland was written of in the Sagas and features a centuries-old escape tunnel.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

These concrete domes were installed on an Icelandic bluff to honor a very specific musical tradion.

This replica Viking village was created for a film that was never shot and is now open to visitors.

This tiny museum's sizable collection is jammed into a former underground public toilet.

These ominous lava formations were said to be an entrance to the netherworld so of course they inspired a famous metal band.

The oldest church in Iceland is one of the few to feature ornate decoration.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Europe's second largest ossuary wasn't discovered until 2001.

A cheeky architectural easter egg.

An existential riddle in the world's largest ancient castle.

This uber-quaint Polish village is known for its habit of painting elaborate floral motifs on just about everything.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

An underground city of salt.

A fake town founded by Western movie stars is now becoming a hip desert community.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.