An ancient Greek monument and a Byzantine church coexist inside this cave.

Underneath one of the region's most historic roads lies the home of Plato's successor.

A former military hospital is now used to study and preserve artifacts of the Acropolis.

This mystical orb covered in strange symbols is thought to have been used in ancient Greek magical rituals.

The site where hundreds of Greeks were tortured by the Nazi secret police is now a cosmetics store.

A sharp sculpture made of thousands of pieces of jagged glass.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

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

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

With no menu and no sign, this 130-year-old taverna doles out affordable home cooking.

An ancient site that has revealed incredible artifacts including portions of the Themistoclean Wall.

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

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

A marvel of Byzantine engineering under the streets of Istanbul.

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

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.

A surprising and unconventional mosque hidden in the subsoil of Istanbul.

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

A fountain standing as a testament to a doomed alliance.

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

A tiny park in the middle of some big power politics.

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.