This beehive tomb built for royalty sat hidden for over 3,000 years.

A short tunnel built straight through a magmatic dike.

Roman ruins found on the outskirts of a small town on the North Wales coast have over time become a strong part of the community's identity.

This Welsh village gave itself a ridiculous name in a publicity stunt a century ahead of its time.

A little-known castle set in a nature reserve.

The remains of centuries of copper mining appear like an alien landscape.

These haunting ruins belong to an ancient village that once had one hell of a view.

Austria's ultra-modern art museum looks like Cthulhu's giant alien heart.

Double spiral staircases are not unheard of, but they are very rare.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

Eyam took steps to quarantine themselves and keep the plague from spreading.

An architectural oddity of six stories, accessed by graceful ramps.

The oldest stone house in Paris was built by its most famous alchemist.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

Abandoned railway line circling the city of Paris.

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

A popular Icelandic children's story comes to life inside this cave.

A functioning Roman-era aqueduct and bridge in rural southwest France.

The site of the first medieval crusade that pitted Christians against Christians.

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

The evocative ruins of a medieval village.

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

A winery built on the site of a Gallo-Roman estate uses historical tools to recreate ancient vintages.

This fascinating abbey is considered the oldest monastery in the region.