Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

The final resting place for the remains of 143 Habsburg royalty.

The beautiful baroque library of the Hapsburg empire.

This massive mural by famed pop-artist Keith Haring was hidden for almost 30 years until its 2018 rediscovery.

A beautifully eclectic mix of architectural styles.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

The world's only museum devoted to the wonders of fluorescence.

The most visited, and possibly most controversial, museum in Germany.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

Giant topiary dog once played a role in a terrorist bomb plot.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

An iconic and controversial ancient Iberian funerary urn with a hauntingly penetrating gaze.

A darkly erotic open-air statuary in Catalonia.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Numerous sculptures set along hiking trails symbolize and idealize the relationship between man and nature.

Earth's rocky history has rarely glittered so brightly as it does in this Spanish museum.

Of course Salvador Dalí lived in a castle...

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

This lucky bronze frog was gifted to Madrid by a casino.

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

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

A landscape decorated with enormous skull sculptures.