This snug medieval lane is one of the narrowest streets in the world.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

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

This Romanian village may have been drowned, but it is long from forgotten.

Climbing to the top of the cathedral's bell tower offers sweeping views of these medieval ruins.

Nine centuries-old fortresses guard the walls of this medieval Romanian city.

This hauntingly beautiful cemetery outside a medieval citadel is full of winding paths and ivy-covered graves.

No one knows who built this strange cave of worship or exactly why.

A medieval church built up to defend its village.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.

Turkish adventurer antiques in the heart of the Grand Bazaar.

The legendary luxury train passage is commemorated with a charming museum inside its former eastern terminus.

An Art Nouveau gem hides beneath the layers of city grime obscuring this once-magnificent building.

No one is sure if the world's fourth-largest diamond had been found in a rubbish heap or was pawned by Napoleon's mom.

1513 Turkish world map, full of European state secrets and snarky commentary.

A sixth-century Byzantine cistern hidden below a modern carpet store.

A section of the long chain that blocked enemy ships from entering Constantinople.

Ancient serpentine sacrifice holder that has stood the test of time.

Quite possibly the oldest love poem known to humankind.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A fountain standing as a testament to a doomed alliance.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.