Beautiful tiles decorate many of the town's surfaces and stand testimony to its glorious artistic history.

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

12th-century holy complex shares land with a natural park full of heavenly waterfalls and raptors.

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

An abandoned Indian-inspired mansion.

Holy Grotto of Montserrat Monastery holds one of Europe's mysterious black Madonnas.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

On La Gomera, "Silbadors" communicate in a 4,000-word language of whistles.

This whimsical winery by Antoni Gaudí looks ripped from the pages of a fairytale.

An architect transformed this abandoned cement factory into his castle-like workshop.

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

"Alleys of Stone" form natural mazes in Spanish natural park.

A Franco-era dam flooded (almost) everyone out of this centuries-old Aragonese town.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

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

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

A landscape decorated with enormous skull sculptures.

At the foot of a waterfall lies a peaceful swimming lagoon and evidence of over 60,000 years of human habitation.

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

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

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

Natural stone arches form a walkable "cathedral" at low tide, then disappear entirely when the water returns.

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