This hill is known for its connection to the occult in Slavic tradition.

The ruins of an abandoned church loom within a picturesque Ukranian village.

A subterranean Holocaust refuge within one of the world's longest cave systems.

This unassuming museum's slogan translates to “there is a limit of sadness, anxiety has no limits."

The largest catacomb system in the world.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

If you want to talk to the Pope you will have to stare down this surreal vision of Jesus rising from a nuclear hell.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

A hidden workshop for creating and restoring Papal mosaic masterpieces.

Breathtaking and huge 430 year old maps of Italy.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

The Vatican's secret porn-festooned bathroom was painted in erotic murals by one of the greatest artists of the Renaissance.

This Swedish sculpture park is a unique combination of ancient ruins and modern art.

This runestone once destroyed by an explosion has been painstakingly reassembled to save its history.

These Bronze Age rock carvings are among the oldest in the region.

These ancient rune stones plucked from the countryside now call this university park home.

A large collection of ancient runestones decorates this university courtyard.

A rare rune stone dedicated to a woman.

A prehistoric geological oddity tucked behind Stockholm's natural history museum.

This 2,000-year-old stone maze is one of the oldest in the country, but its purpose is still a mystery.

This museum of Viking vessels allows visitors to take a replica out for a spin.

This serene wooded hilltop has a dark history as the climactic point of the Swedish witch trials.

A catapult rock from Gotland’s 13th-century civil war is still lodged in Scandinavia's best-preserved medieval city wall.