What looks like a normal building is really a hollow facade hiding a subway vent.

This medieval tower is all that remains of the castle where Joan of Arc was held before being burned at the stake.

The sunken structure looks like the victim of a catastrophic flood.

This futuristic observatory at the top of the Pyrénées offers unrivaled views.

This crumbling, graffiti-covered mansion sits tantalizingly within reach of the proletariat who frequent a public park.

A centuries-old complex of hand-dug stone chambers has sheltered locals in times of trouble.

A colossal sculptural lion built by the same man who designed the Statue of Liberty.

If they push on just the right spot, even the weakest person can move this titanic boulder.

Statue of a decomposing prince that once held his heart in its hand.

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

The Argonaute submarine was the French navy's pride and joy in the 1950's.

A bike train runs along a disused railway line through the tranquil French countryside.

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

The world's tallest bridge is also possibly the most elegant.

The world's largest reflecting pool is just two centimeters deep.

The Cimetière des Chiens et Autres Animaux Domestiques is one of the oldest pet cemeteries in the world.

The great Italian Renaissance painter was laid to rest here in the Chapel of Saint-Hubert.

Sleep in a climate-controlled plastic bubble for the night.

An icy lake tucked among jaw-dropping alpine panoramas.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

Science fiction's grandfather has a fittingly marvelous tomb.