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

Two small chapels housed inside an ancient tree.

Historic medieval fortified city in southwest France.

An icy lake tucked among jaw-dropping alpine panoramas.

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

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

A Gothic cathedral created from volcanic rocks.

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.

Do these monsters look familiar? The gargoyles on this church are all from pop culture.

The largest underground church in Europe.

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

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

A font of vintage porn on the silver screen.

Hidden away in a modern library are the remains of one of the 18th century's most celebrated wunderkammers.

The only remaining collection of flayed figures made by French "madman" Honoré Fragonard.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

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

A cave dwelling that was started by the Celts, expanded by monks, and finished by knights.

How did a French journalist’s grave become the sexiest statue in the cemetery?

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

Ancient paintings known as the "Sistine Chapel of Cave Art."