A completely underwater art museum sends a stark message about humans' impact on the environment.

An isolated village literally built into the crevices and rock formations of a mountain.

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

A Spanish town built into the cliffs.

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

This Navarrese cave's history of witchcraft and pagan ritual is not just embraced, but recreated each year.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

A landscape decorated with enormous skull sculptures.

A gravity-defying "devil's bridge" that has a surprising architectural feature for its stability.

One of Europe's largest supercomputers is housed inside of a disused chapel.

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

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

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

Turntable anonymously received orphans, alms, and groceries.

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

A stately palace has been converted into the world's largest cannabis museum.

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.

Spanning the El Chorro gorge, this pathway used to be one of the most dangerous crossings in the world.

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

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

An enchanting monastery in the Spanish countryside appears lifted from a fantasy tale.

Wonderland replication in progress by one persistent man.

A museum dedicated to the Spanish occult in a town that was terrorized by the Inquisition.

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