Cathedral-like Victorian vaults are hidden within this iconic bridge.

A radio telescope for listening to the stars, based in one of the cloudiest countries in the world.

Former hunting lodge of a duke who was an avid collector of impressionist works.

A magical, macabre wax museum, beloved by locals, uses real artifacts to depict an assassination from the French Revolution.

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

The Sun King's military models, saved from the Louvre.

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

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

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

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

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

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

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

The largest medical and anatomical collection in France lies hidden from the public.

The curious underground history of keeping Paris clean.

Behind the pink curtain, Au Bonheur du Jour, an art gallery of erotic archives.

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

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

A haunting collection of the vanished and disappearing natural world.

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

One of the oldest medical collections in Europe focusing on rare surgical instruments.

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

France's most famous cemetery, with some of its most curious tombs.

Abandoned railway line circling the city of Paris.