The intricate geometry inside this Baroque-style dome was designed to create "terror of the human soul."

This building has a giant piercing through one of its corners.

This fountain is dedicated to the workers who perished constructing the Fréjus Rail Tunnel.

The world's largest second-hand graces a clock surrounded by constantly changing flower beds. 

This stone in Lake Geneva was once the reference point used to determine altitude in Switzerland.

A plain wooden seat that once belonged to one of the most prominent figures of the Protestant Reformation.

One of the longest wooden benches in the world snakes around Geneva's Treille Promenade.

On the side of a building, a depiction of the woman who became a local legend by tossing soup out her window.

An opulent monument built for a duke who donated his entire fortune to the city of Geneva.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

A beautiful Victorian statue shows France's enduring love of the rhinoceros.

This emotive sculpture was originally created for the 1878 World's Fair.

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

Site of a classic 19th-century physics experiment to prove the earth is rotating.

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

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

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

The celebrated eyesore created by starry-eyed sweethearts.

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

A museum dedicated to linguistics, from how babies learn to talk to endangered and extinct languages.

A poem by Arthur Rimbaud is inscribed on the wall of a street that, while it is only one block long, plays a key role in multiple novels.

An unusual number plate signifies the building's saucy past.

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

Notorious artist squat renovated into legal studios.