Built on a medieval synagogue, this church has a burial crypt, tunnel system, and Jewish ritual bath hiding deep underneath.

This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

Why a column on the entrance is inscribed with a verse from the Quran is one of Sicily's many mysteries.

This mosaic-lined medieval church was built by the world's first admiral and still holds mass in ancient Greek.

The world's most active stratovolcano is almost always erupting.

Formerly Yugoslavia's "forbidden island," this sleepy little city still holds the abandoned remains of military strongholds.

This sprawling market is a one-stop shop for traditional Kazakh foods, from mare’s milk to sheep’s head.

A former bank seized as a sniper vantage point during the Bosnian War is now a secret graffiti art gallery.

Bridge that died in war and was resurected.

The sad remains of a monument to martial arts legend and movie star Bruce Lee—in the middle of Balkans.

In Kazakhstan, a colorful cathedral with many lives once survived the most powerful earthquake in the region.

This Soviet statue is based on a piece of propaganda that's been elevated to national myth.

This vast masterpiece of Moroccan architecture spreads across 20 acres.

Fortune tellers, snake charmers, poets, and storytellers all gather on this historic square in Morocco.

The largest madrasa in Morocco once housed more than 900 students within its exquisite walls.

Deliberately hidden for centuries, the magnificent Saadian Tombs were eventually uncovered in 1917.

Island wonderland for communist autocrats.

Trimmed trees grow alongside the graves like topiary tombstones.

A musical instrument played by the sea.

The big toe of this towering monument to a Croatian national hero is worn from years of superstitious rubbing.

Built entirely of interlocking pieces, construction of this Chinese Muslim house of worship required zero nails.

Austria's ultra-modern art museum looks like Cthulhu's giant alien heart.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

Humble beginnings for one of the world's most famous scientists.