One of Mexico's least-visited archaeological sites is tucked away inside a theme park.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The Lone Star plaque hangs in a bombed-out bunker in Normandy to honor a Texan colonel's heroic actions on D-Day.

Inaugurated in 1921, this is one of many statues in France dedicated to the people who died during World War I for their country.

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

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

Real bones which are said to have belonged to a Polish dragon.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

A fearsome dragon clings to a corner of Munich's city hall.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

The Pope’s secret escape route.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Breathtaking and huge 430 year old maps of Italy.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

These pretty kitties killed and ate as many as 135 railway workers.

To find the "unicorns of the deep" you've got to go downstairs.

Years of archaeology, just chillin' by the water cooler.

This awkward aquarium sculpture is one of the strangest statues in Chicago.

Chicago's Navy Pier on Lake Michigan was a training hub for aircraft carrier pilots during WWII.

This sprawling mini-golf empire is an impressive testament to a disappearing attraction.

Robots, lasers, and whoopee cushions, oh my!

A wonderfully curated used bookstore in an airport.