A historic castle that served as a backdrop to part of an elaborate extraterrestrial hoax.

An open-air sculpture museum in a park in Alcorcón.

Nicknamed the "Spirit of Paul Klee," this colorful apartment building features an array of multicolored panels.

The magic of Spanish aviation housed under one roof.

Many miles south of Loch Ness, a similarly-named sea monster stands at the center of a roundabout.

An ode to the famous Las Vegas signage.

This technological marvel is one of the world's first 3D-printed bridges.

This postmodern apartment block was designed to be a vertical neighborhood.

This amazing abuela became a diehard metal fan late in life and an icon of Madrid's '80s rock scene.

A magnificent, long-abandoned castle built in the wake of the reconquest of Spain.

A model solar system adds a celestial touch to this suburban park.

The small Spanish town that played an important role in a human's first steps on the moon.

Designed in the Romanesque style, this structure was once a fortress monastery.

This narrow path was cut right into a French mountainside to feed the country's early naval expansion.

This 18th-century project to build the world's tallest gravity dam was never completed.

These Bullet-scarred bunkers are haunting reminders of the Spanish Civil War.

Cursed swimming pool left abandoned is now a favorite of filmmakers and ghost hunters.

An open-air "garden" of mural art that changes weekly.

One of Antoni Gaudí’s earliest buildings, built between 1886 and 1890 for the industrialist Eusebi Güell.

A bookstore dedicated to the intersection of comedy and art.

This colorful statue welcomes visitors to a Barcelona park.

This cemetery features modernist statues as strange as its name.

Occupied for six centuries by Franciscan Order nuns, this monastery is an amazing ode to Catalán Gothic architecture.

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