The castle was reconstructed to fit Kaiser Wilhelm II's romanticized vision of the Middle Ages.

A sanctuary for wolves in a community which once trembled in fear of the murderous "Beast of Gévaudan."

The largest crypt ever constructed in France was built in the 11th century on an ancient Druid sacred site.

Legend has it this 11th-century castle was paid a visit from the devil.

French commune at the heart of conspiracies.

Series of underground houses inhabited continuously for centuries.

This 14th century wine cellar is home to the oldest barrel-stored wine in the world.

An ancient ossuary in Rouen.

The opulent home that inspired Tintin's Marlinspike Hall and the adventures within.

Green labyrinth formed by a karstic maze hidden in a preserved oak forest.

The birthplace of the ferocious William the Conqueror, this castle is awash in medieval history.

Despite centuries of architectural innovation, this French castle is being built like it's the 13th century.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

The historic Masonic Lodge in which the first-ever female Mason was initiated.

Miles of man-made caves and tunnels are currently used for cultivating mushrooms.

Tables of secondhand books fill the inner courtyard of this 17th-century stock exchange.

A unique underground structure dating back to the 1st century BC.

Trek into the depths of the cave where 17,000-year-old paintings exist alongside 400-year-old graffiti.

Nicknamed the "Museum of Horrors," this French anatomical collection has been fascinating visitors for over a century.

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

A French library that makes sure its love of books is writ large... giant in fact.

Bits of architecture from a town destroyed in World War I now decorate this hotel garden.

An art world insider finds himself battling for his artistic home.

These crumbling Nazi artillery bunkers are now fair game for massive graffiti projects.