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

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

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

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

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

The very center of Paris is surrounded by a bevy of strange good luck rituals.

This frog-themed restaurant was frequented by Picasso, Saint-Exupéry, and more.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

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

A museum on the history of Paris, including a set of Napoleon's toiletries, Proust's room, and relics of the Revolution.

The history of radiation is on safe display at the foot of a radiation science laboratory.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

Indents in the pavement are all that remain from a grisly death machine in Paris.

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

Walk upon the mementos of the dead in this Parisian courtyard paved with medieval tombstones.

France's national museum of scientific and industrial instruments.

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

A haunting collection of the vanished and disappearing natural world.

The oldest stone house in Paris was built by its most famous alchemist.

Abandoned railway line circling the city of Paris.

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

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