These three pillboxes still remain as a witness of the Spanish Civil War in a park of Madrid.

Just like in Hollywood, Madrid has also a forgotten walk of fame.

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

The abandoned ruins of a beautiful medieval castle just outside Barcelona.

Mountain where Jesus was first tempted by the Devil.

One of Antoni Gaudí's least-visited works, an homage to Catalan patrimony that mixes neo-Gothic with Modernista forms.

One of the most photographed buildings in a city known for its Modernista architecture is an abandoned squat.

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.

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

Gaze upon chocolate sculptures depicting everything from chariot races to Gaudí's famous church at this shrine to sweets.

This cemetery features modernist statues as strange as its name.

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

This cafe offers a curated collection of treats and tipples made by monks and nuns.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

A once-secret library of Freemason history in Catalonia.

For decades, Puerta del Sol has been illuminated by a giant, guitar-wielding bottle of sherry.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

A reproduction of the famous prehistoric cave paintings is hidden underground at the National Archaeological Museum.

A subterranean relic of the Spanish Civil War hides below this picturesque park.

Madrid's last horchata kiosk is a blue-and-white beacon of refreshment.

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

This lucky bronze frog was gifted to Madrid by a casino.

The little church's beautifully frescoed ceiling has earned it the nickname “the Sistine Chapel of Madrid.”

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.