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

Catalonia Tradition: Beating the hollow Christmas log until it defecates in your fireplace.

Two towns are linked by an engineering marvel masquerading as a boring suspension bridge.

A historic Christian shrine nestled within a spectacular natural cave.

Giant topiary dog once played a role in a terrorist bomb plot.

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.

18th century anatomical amphitheater of the Royal College of Surgery of Barcelona.

A site where “the ravages of the war are more striking…than any other place in contemporary Spain.”

A once grand hotel now sits eerily abandoned in the Catalan countryside outside Barcelona.

Stunning Roman aqueduct used for 1900 years and still standing.

A former steam-powered mill from the 1800s is now an industrial park with a giant steel dragon slide.

A Spanish forest is filled with mysterious stone carvings.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

A gravity-defying "devil's bridge" that has a surprising architectural feature for its stability.

Commonly acknowledged as the only public monument to the Devil himself.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

A lush indoor jungle fills this bustling Madrid transportation hub.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

Bask in the 19th century grandeur of an eccentric Freemason millionaire's private gardens.

Hundreds of stone stairs and a winding medieval bridge connect this haunting Spanish island to the mainland.

This semi-secret storybook hedge maze is also the oldest garden in the city.

This imposing modern citadel started out as a home renovation project.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.