A memorial to the nearly 10,000 American soldiers laid to rest on the beaches of Normandy during WWII.

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

This enormous "cloth of the conquest" depicts the Norman invasion of England in mind-blowing detail.

A swath of France so devastated by war it is still forbidden to go there.

Hundreds of secret cabinets built into the walls of legendary poisoner's private work room.

This French castle is said to have once held the Holy Grail but is now a gorgeous mountaintop ruin.

An ancient monastery, a locked room, and a mysterious book heist.

This demon atop the Notre-Dame de Paris looks utterly bored.

At Monet's beloved home you can still see the Japanese bridge, waterlilies, and weeping willows that were the subjects of some of his most iconic paintings.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Monasteries on rock pillars, once accessible only by frayed ropes.

The hallucinogenic center of the ancient world.

One of the world's largest ancient burial mounds.

Not quite the menace it once was, this monster still has some chops.

A centuries-old bar once frequented by Picasso, Hemingway, and Dalí.

This Arab fortress was once the largest citadel in Western Europe.

Stunning Roman aqueduct used for 1900 years and still standing.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

A boulder in the Churchyard of Down Cathedral marks the legendary burial place of "The Apostle of Ireland."

The ruins of this medieval castle in Northern Ireland have inspired artists from C.S. Lewis to Led Zeppelin.

This castle has links to Portugal’s founding and struggles for independence.

This modern French ossuary contains the jumbled bones of 130,000 WWI soldiers.