A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

BDSM, 1930s Style.

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

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

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

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

This museum in a Paris apartment gives a unique look at the iconic French singer's life.

The former home of France's controversial pop maestro is almost completely covered in ever-changing tributes and graffiti.

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

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

This banal Parisian entranceway is not what it seems.

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.

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

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

Where the high court feasted, frolicked, and high courtesans put their royal lovers' diamonds to the test.

Noirish green neon marks the location of one of the oldest private detective agencies in France.

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

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

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

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

One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

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

The first green space constructed on an elevated viaduct.

Paris' fabled purveyor of exotic taxidermy and natural history curios.