The experimental test tracks of a retro-futuristic monorail still stand in the French countryside.

This church sits upon a peaceful hill and a long, turbulent history.

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

A beautiful and classically designed villa, with an hourly infestation of monsters.

Perhaps the most beautiful of preserved saints, with a little help from Paris.

This whimsical castle of grottoes was the labor of love of a French postman, and one of the greatest achievements of outsider architecture.

Museum on French naval history, with magnificent figureheads, a historic diving suit, and a boat used by Napoleon.

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

This Parisian café sticks almost exclusively to an ethos of reuse.

This museum houses an imposing skeleton army comprised of creatures great and small.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

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

A haunting collection of the vanished and disappearing natural world.

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

The remaining relics of the patroness of Paris lie in a chapel under a striking double spiral staircase.

A 400-year-old church covered floor to ceiling in ex-voto offerings from the faithful.

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

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

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

The celebrated eyesore created by starry-eyed sweethearts.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

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

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

This bridge was constructed from the rubble of the infamous Bastille.