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

This ancient theater was once the home of fierce gladiatorial battles.

This whimsical castle of grottoes was the labor of love of a French postman, and one of the greatest achievements of outsider architecture.

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

Lyon's miniature version of the Eiffel Tower was built as a statement in support of French secularism.

A colorful piece of contemporary art cheerfully clashes with Lyon's historical architecture.

Massive puppet-automaton machines created by French artist collective Machines de l’Ile.

Do these monsters look familiar? The gargoyles on this church are all from pop culture.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The natural history museum displaying the British bird collections and dioramas of Edward Booth, free of charge.

The rotting skeleton of a shoreside fun fair that was destroyed by fire and storms still haunts the Brighton ocean view.

The place where houses are born.

Catering to broken dolls for almost 200 years, this repair shop is now a charnel house of doll parts.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

A neolithic tomb converted into a tiny chapel.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

This crumbling Portuguese ruin overlooks the populace it once ruled.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Remains of the artificial harbours invented for the Allied invasion of Normandy can still be seen at sea.

A castle-like sea fort from the 17th century is now a museum to oyster farming.

This black church sits alone among a field of lava rock.