A huge Megalithic chamber tomb located behind a cafe.

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

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

There has been an astronomical clock on this spot since the 14th century.

One of the world's largest collections of pharmaceutical artifacts.

A sandstone block marks the alleged spot where the legendary writer was conceived.

Natural mummies hidden in the crypt of a medieval French church.

A cave dwelling that was started by the Celts, expanded by monks, and finished by knights.

Ancient paintings known as the "Sistine Chapel of Cave Art."

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

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

A quarry cum sculpture park where the works of art are chiseled into the very walls.

The largest underground church in Europe.

A 14th century bridge built as a fortress, where the devil lurks on one of its towers.

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

Series of underground houses inhabited continuously for centuries.

This French "sea of rocks" is packed with stunning rock formations and its own medieval castle.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

A private garden of sculptural eccentricities.

These medieval ruins have survived since the 12th century, even providing shelter from the Nazis.

The castle where the Marquis de Sade lived out his darkest fantasies.

One of the largest ochre quarries in the world, hidden in a limestone landscape.

Longest canal tunnel in the world, abandoned in the 1960s.

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