The streets of a sleepy Spanish town proudly exhibit some of the world's finest graffiti.

The only museum dedicated entirely to the dry stone walling technique.

This ancient tunnel is one of the most important examples of Roman hydraulic engineering in Spain.

Geological storytelling.

A darkly erotic open-air statuary in Catalonia.

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

The Gaudí-inspired building that was the start of Terrassenc modernism.

Designed by Gustave Eiffel before his famed tower.

A Romanesque tower appears when water levels drop.

A Spanish forest is filled with mysterious stone carvings.

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

Two large eyes painted anonymously on a mountain overlooking the city pay homage to an old legend.

Walls of stone rise up from sinkholes caused by underwater erosion.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.

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

A series of recreated fortifications mark George Orwell's path through the Spanish Civil War.

Wonderland replication in progress by one persistent man.

Famed architect Antoni Gaudi built this generous thank you gift to a friendly host who housed him during a job.

This 15th century pharmacy displays a beautiful collection of ancient medicine jars.

The world's largest solar furnace uses 10,000 mirrors to concentrate the sun's rays to generate power.

A well-preserved medieval village nested on a rocky outcrop and surrounded by a network of cliffs, natural bridges and canyons.

Half a century after it was abandoned, this ghost town is coming back to life.

The Nobel-Prize-winning author of The Stranger is buried beneath a simple gravestone in a sleepy French village.

Sculpture of a legendary French dragon.