This failed condo development was reborn as a street art hub.

Continuing the tradition of the dime museum in style.

A beautiful little museum hidden away in the heart of Barcelona holds a treasure trove of Ancient Egyptian artifacts

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

An eclectic collection of thousands of items owned by the sculptor Frederic Marès.

For one day every month Barcelona's Estació de França transforms into a market for model trains.

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.

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

A temple to modernity, tucked away amid Barcelona's more well known museums.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

A stately palace has been converted into the world's largest cannabis museum.

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

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

Mountain where Jesus was first tempted by the Devil.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

A beautiful but toxic fountain of mercury.

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

One of Madrid's oldest trees, with a long and colorful history, resides in El Retiro Park.

An old, deep well, connected with a miraculous, divine rescue and the patron saint of Madrid.

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

Stuck in the middle of a modern Madrid city block are the remains of a 19th century sports complex.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

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