A Byzantine-era church hidden in a wooded area below the Acropolis.

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

Where commuters walk through remnants of an ancient Greek necropolis.

The ruins of an ancient Roman tomb hidden in the basement of a trendy clothing store.

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

An ancient octagonal weather station named for the eight Greek gods of wind.

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

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

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

The hallucinogenic center of the ancient world.

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

A mysterious spirit totem at the edge of Navajo lands.