A marvel of Byzantine engineering under the streets of Istanbul.

Legend says if you stick your thumb in the hole and it gets wet your wish will be granted.

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

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

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

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

Once described as the "Eagle's Nest," this ruined ancient city rests on a remote mountaintop.

These artifacts were discovered during the construction of the airport, with some dating back to the Neolithic period.

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

Legend says this sacred tree was a gift from goddess Athena.

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

The ruins of this ancient fortification wall sit in the middle of a quiet, residential intersection.

A spectacular cave and a beguiling lake.

A building so large that it has its own weather.

Home to an endangered salamander, a full moon celebration, and a large spring-fed outdoor swimming pool.

The world's largest military aircraft cemetery.

Meet 'Big Josh,' the 20-foot-tall muffler man.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

A second generation sun-powered marvel lights up the night.

In a city filled with Frank Gehry buildings, one stands out as one of the architect's weirder works.

60 feet of towering steel balances gracefully.

From pre-war whiskey cocktails to prohibition-era speakeasy secrecy, this bar has seen it all.