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

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

A marvel of Byzantine engineering under the streets of Istanbul.

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

A charming beach town in Turkey captures all the colors of the rainbow.

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

A sacred lake with thousands of sacred carp and a biblical history.

The largest Neolithic ruins in the world hide a notably clean prehistoric metropolis.

Mausoleum and Holy Seat of Antiochus I of Commagene.

The best-preserved ancient theater in the world.

While not Turkey's deepest underground city, this subterranean redoubt is the largest.

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

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

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

According to the legend, this structure was built in a single night with the help of the devil.

This monumental fountain has moved around the city multiple times.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

This medieval city gate is now a blend of the past and the modern world.

An unusual "skull with ears" sits in the crypt of this small church tucked away at the end of a narrow alley.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

This unique collection collects pieces of art etched into thin pieces of stone.

For decades, this waterfall remained hidden because of an artificial dam.