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

Visitors dating back to the 1600s carved their marks in the stones of the iconic tower.

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

On a cornerstone of the City Museum is the head of a monstrous serpent stolen from an Aztec pyramid 400 years ago.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

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

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

Even France's favorite aquatic son Jacques Cousteau, couldn't get to the bottom of it.

The smallest port in France is named after the pirate who created it.

An isolated 17th-century chapel on a remarkable site once dedicated to Celtic sun worship.

Abandoned railway line circling the city of Paris.

Notorious artist squat renovated into legal studios.

Bangkok celebrated its shifting monarchy with a militaristic homage to democracy.

Four antique Baldwin trains are kept on display in the Mal Tiempo train depot.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

Castro's communist ice cream mothership has been serving five-scoop "salads" for over 50 years.

An old slave lookout in Cuba's historic sugar cane fields.

After the Cuban Revolution, the famous rum company had to leave their swanky headquarters behind.

Where layer cakes tower above one’s head and there is never a shortage of icing.

The burial place of some of Mexico's most prominent residents is full of macabre stories and hidden masonic symbols.

Diego Rivera's massive tiled fountain and failed infrastructure project.

The famous artist couple lived and worked here, in two different houses connected by a bridge.

A museum in the former home of Marxist revolutionary Leon Trotsky.

This incredible college library is a visual masterpiece of mosaic art. It also looks kind of like a giant boombox.