The best-preserved ancient theater in the world.

Step back in time and witness the fall of Constantinople.

The most metal church of all time was built in record time because of an international, pious pissing contest.

Flames have been burning within this mountain for more than 2,500 years.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

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

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

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

A Turkish ghost town abandoned in a population exchange with Greece.

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

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

This famous city eluded concrete detection until the early 2000's.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

This hunter-gatherer architecture is believed to be the oldest religious complex known.

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

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

The ornate miniature mansions were built for Istanbul's feathered residents.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

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

A marvel of Byzantine engineering under the streets of Istanbul.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

Historic beer hall in Bucharest with magnificent stained glass and a lively folk band.

Romania's triumphal arch looks out over Bucharest.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.