Abandoned Roman Catholic chapel abused by Satanists before being restored.

Overshadowed by other, more famous Maltese catacombs, this ancient burial chamber has one of the best examples of a ritual agape table.

This prison on the Maltese island of Gozo is almost 500 years old, and they have the graffiti to prove it.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

At more than 5,000 years old, these structures are among the oldest free-standing stone buildings in the world.

These temples are among the oldest free-standing stone buildings in the world.

The remains of a 1st-century aristocratic Roman town house featuring beautiful well-preserved mosaics.

The Jesus tree of Malta bears a striking resemblance to Christ on the cross.

A centuries-old forgotten underworld lies beneath Malta.

A hidden tunnel of bones in one of Malta's oldest churches.

This subterranean necropolis holds three floors of antler-dug grave caves.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

A museum of alchemy and a basement laboratory all housed in an ancient building in a Gothic tower.

An army of sleeping knights sculpted by a self-taught local artist beautifully depict an old Czech legend.

This spooky statue sits outside a famous Prague theater.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

A cheeky architectural easter egg.

A church of bones, decorated with 40,000 human skeletons.

Countless grotesque faces stare out from this eerie Prague art wall.

A Jenga-style cylindrical tower of books that appears to go on forever.

The discovery of this Neolithic settlement, which contained a Stone Age "cathedral," threw archaeologists for a loop.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.