An ancient and majestic fortress that played an integral role in Portugal's road to independence.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

A unique seaside cave where Aleister Crowley faked his own death.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This small chapel is built of human bones and decorated with a golden skeleton.

An old wool-washing house filled with Fluxus contemporary art.

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

Dead weights honor the dead of Portugal's fishing industry.

This architectural beauty is the home to a personal collection of more than 600 examples of mechanical musical instruments.

There was a top secret plan during World War II to seal a group of soldiers inside the rock.

Infamous and now demolished panopticon prison built by its former inhabitants.

This abandoned mansion has a window for every day of the year, and is a temple for ghost hunters.

This abandoned racetrack looks like it is set to hold competitions in the apocalypse.

The tiny Spanish village that long refused to change its outrageously anti-Semitic name.

This rough experimental house was created by flooding a dirt hill with concrete.

The ruins of a bombed medieval village memorialize the destruction of the Spanish Civil War.

"Satisfying" is a good way to describe these beautifully aligned rows of Spanish mills.

An impressive home made of stone, carved more than a century ago.

The deserted remains of a luxury hotel turned hospital ward.

Remote, beautiful, and stigmatized, Las Hurdes is Spain's version of Appalachia.

This 47-story "M" needed 20 years to be completed

Abandoned 18th century weapons factory in the Aezkoa Valley.

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

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