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

The recovered bones of martyrs slaughtered during The Terror are on display in this church crypt.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

The headless bodies of more than 1,300 guillotined victims of the Reign of Terror are buried here in mass graves.

This stunning natural double arch, the largest in the Alps, went undiscovered until 2005.

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

This off-limits room in the National Library of France is home to a system of pneumatic tubes, once used to bring books to readers.

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

One woman's decades-long obsession with the "La Fée Verte."

Museum on French naval history, with magnificent figureheads, a historic diving suit, and a boat used by Napoleon.

Beautiful carved tunnels.

Sleep in a climate-controlled plastic bubble for the night.

This professional clown's home is an outsider art wonderland.

The fantastic architectural models of a French traveler.

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.

A popular shrine where the Blessed Virgin allegedly appeared in 1830, displaying a holy armchair and two incorruptible remains of Lady Saints.

This salt marsh in Southern France is as pink as the flamingos that inhabit it.

An aluminum skeleton brings Chinese mythology to the French shore.

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

Two awe-inspiring globes from the reign of the Sun King hang from the ceiling of France's national library.

Ghosts of France's colonial past.