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

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

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.

Stunning Roman aqueduct used for 1900 years and still standing.

The earliest known map to show America, discovered by accident at a Paris bookshop.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

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

Village situated on a narrow volcanic escarpment.

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

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

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

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

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

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

Turntable anonymously received orphans, alms, and groceries.

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

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

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

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

A lush indoor jungle fills this bustling Madrid transportation hub.

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

Week-long block party becomes a competition for the best decorated street.

An ancient Egyptian temple in the middle of Madrid, Spain.

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