Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

This magnificent castle grew from a small Moorish fortress, and reportedly inspired two iconic Disney castles.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

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.

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

An early 20th-century bullring converted into a modern shopping center.

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

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Its appearance in "Game of Thrones" may spur on the long-awaited restoration of this medieval shipyard.

The final resting place of the great navigator, or maybe his brother.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A park where people have been going to feed friendly pigeons since the 18th century

An exhibition devoted to the life (and posthumous taxidermy form) of the last known representative of the Pinta Island Tortoises.

The "lovely red Vega" of the legendary record-settling pilot.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

Home to items never before seen by the public.

Perhaps the most scandalous statue of America's first president.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

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

A place to eat for on-the-run agents and espionage enthusiasts.