High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

This massive library holds what was once the largest book collection in the world.

France's most famous cemetery, with some of its most curious tombs.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

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

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

Skulls from the plague of 1656 and World War II bombings are united by a cult dedicated to caring for the ancient dead.

These "anatomical machines" are only one of the many strange items in this Italian crypt.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.