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.

On rare days, this abandoned castle's gatekeepers open its doors, revealing the eye-popping splendor hidden inside.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

The romantic botanic tunnel feels like a well-kept secret.

A "miracle" that seems to produce more holy fistfights than holy revelations.

The only quarter of the Old City not dedicated to a major world religion.

The home of the Dead Sea Scrolls is an abstract modernist dream.

A marvel of Byzantine engineering under the streets of Istanbul.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

This historic hotel preserves many treasures from its heyday hosting passengers on the Orient Express.

Roman ruins top white travertine terraces formed by ancient hot springs.

The best-preserved ancient theater in the world.

This arch granting triumphal entrance into Antalya was designed to honor the emperor's visit.

The elliptical citadel resisted the advance of the mighty Ottomans several times, thanks to the military prowess of the "Dragon of Albania."

Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

This 13th-century monastery chiseled into the side of a mountain is equipped with a bridge that can be lifted to protect against raids.

The hallucinogenic center of the ancient world.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Heralded as the world's first theater, these ruins are often overlooked as they reside in the shadows of the Acropolis.

A striking symbol of the Bulgarian capital.

This once-derelict building is now one of the most beautiful bookstores in the world.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

Something's watching you.