Space-age monument to an early 20th-century uprising.

The celebrated eyesore created by starry-eyed sweethearts.

A magical, macabre wax museum, beloved by locals, uses real artifacts to depict an assassination from the French Revolution.

This bridge was constructed from the rubble of the infamous Bastille.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

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

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

The world's first electric battery-powered submarine.

Possibly the oldest masonry dam in all of Europe.

An enchanting landscape of ancient sandstone structures eroded into otherworldly shapes.

A celebration of solstice followed by a fiery purging of evils.

A daily pyrotechnic celebration marks a beloved tradition during Valencia's festival season.

This 47-story "M" needed 20 years to be completed

Vibrant street art created with mixed media.

An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

Geological storytelling.

Spain's stunning solar energy plant.

The oldest Roman lighthouse still in use.

The Cathedral of Salamanca has a number of unusual carvings but none so surprising as a modern astronaut.

Devastated landscape used for hundreds of years by the Romans as their primary mining site.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

Stunning Roman aqueduct used for 1900 years and still standing.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

Cliffside houses provide a spectacular view from their perch above the valley.