A mosaic-tiled house built by graveyard sweeper Raymond Isidore.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.

The floorboard scrawling of a tragic madman is on public display outside a Paris hospital, much to the dismay of its opponents.

This French castle is said to have once held the Holy Grail but is now a gorgeous mountaintop ruin.

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

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

Got apples?

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

These quaint French houses dangle precariously over a precipice.

Saintly bones pressed into a wax effigy of a Catholic superstar.

This surreal statue brings a famous French novel about a supernatural cad to arresting life.

Beautiful carved tunnels.

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

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

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

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

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

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

This natural French spring has been turned into a magical grotto by Roman and medieval constructions.

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

A Gothic cathedral created from volcanic rocks.

Historic medieval fortified city in southwest France.

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

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.