This grandiose staircase was part of the revival of a medieval Spanish architectural style combining Christian and Islamic influences.

This multi-level, aqueduct-footbridge hybrid is one of the greatest works of the Spanish Renaissance.

For centuries, the largest Arab bathhouse in Spain was hidden under a palace.

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

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

The final resting place of the great navigator, or maybe his brother.

The world's largest wooden structure.

An eerie collection of the surviving structures from a past celebration of the future.

Considered the birthplace of the Copper Age and Bronze Age, the river is tinted red from 5,000 years of mining.

A striking public sculpture representing the period of martial law in Communist Poland.

It’s a painted window that looks completely real, hiding on a building in the market square.

The silly symbol for an underground protest group is now scattered around the city.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

A plaque marks the spot where the saint was shoved off the Charles Bridge and into the river.

Macabre astrological automaton clock dating to the late 1400s.

The statue of a cursed knight is said to come to life every 100 years.

A surreal statue honoring Prague's favorite literary son.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

A museum that chronicles the history of the Nuremberg Trials for Nazi war criminals in the building where the trials were once held.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

It's good luck to be mocked by this monkey.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.