Beautiful carved tunnels.

The former home of France's controversial pop maestro is almost completely covered in ever-changing tributes and graffiti.

Hundreds of secret cabinets built into the walls of legendary poisoner's private work room.

Skeletons, medical artifacts, and other obscure and precious treasures all displayed in a wooden pharmacist's cabinet.

This little-known relic crypt holds stolen parts of a Roman Empress.

Avant garde house of Pierre Cardin on the Cote d’Azur.

The Cimetière des Chiens et Autres Animaux Domestiques is one of the oldest pet cemeteries in the world.

The fantastic architectural models of a French traveler.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

Massive puppet-automaton machines created by French artist collective Machines de l’Ile.

For hundreds of years, automatons moving to metallic music have been marking the passage of time.

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

This modern French ossuary contains the jumbled bones of 130,000 WWI soldiers.

An all-American grocery store in Paris sells U.S. "cuisine" like Pop-Tarts and Heinz ketchup to homesick ex-pats.

Pitié-Salpêtrière was the dumping grounds for women who received the dreaded diagnosis of "hysterical."

A subterranean shelter remains intact under a busy Paris railway station.

Monsters and miniatures are held in equal esteem at this wondrous museum.

A font of vintage porn on the silver screen.

In the best of all possible worlds, everyone will get a chance to see this statue in which Voltaire's heart is interred.

Two small chapels housed inside an ancient tree.

A lone cannonball remains lodged in the walls of the Hotel de Sens as a sober reminder of a revolution.

The famous winding walk at Chartres is surrounded in mystery and myth.

Where the high court feasted, frolicked, and high courtesans put their royal lovers' diamonds to the test.

A 14th century bridge built as a fortress, where the devil lurks on one of its towers.