Gladiators battle and chariots race daily in the ruins of a once-great Roman city.

A more chill but no less fascinating version of the famous ancient archeological site.

An ancient capital city that dates back 3,000 years and harbors many surprises.

The world's largest frame offers spectacular views of the city's past and present.

A preposterously luxurious hotel with gold-plated iPads, Rolls Royce chauffeurs, and a staff that trains by watching "Downton Abbey."

A symbol of Texas pride.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

This sculpture forces visitors to confront their relationship with space.

This working class sculpture pounds his hammer all the livelong day.

The tech giant built three enormous glass orbs in Seattle so employees could work inside a rainforest greenhouse.

A wall of chewing gum moonlights as collective art.

A six-story-tall golden pyramid, surrounded by a moat.

This striking art museum holds an amazing series of curiosity cabinets.

A morbid gateway to an Alaska town prides itself on the hunting history it represents.

The first mosque in the world to receive electricity.

This picturesque monastery at the base of a cliff is a peaceful oasis open to all visitors.

The remains of the last Bosnian fortress to fall to the Ottomans are still standing.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

This brutalist monument is inscribed with 9921 names of Yugoslav partisans who perished during WWII.

This cluster of little wooden huts once ground local farmers’ wheat into flour during the days of the Austro-Hungarian Empire.

Rotterdammers' dirty minds gave this Santa a dirty nickname and cursed it to a life of wandering.

These slanted cubic abodes are a creative if odd solution to a zoning pickle.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

This cheese shop also houses a museum devoted to Dutch dairy.