The site where the summer solstice helped ancient Greeks sync the lunar and solar calendars.

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

These caves secretly held national treasures during World War II.

Rest stops along this pathway offer some of the best views of the Acropolis of Athens.

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

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

This gem is often wrongly overshadowed by the larger, newer Metropolis church in Athens.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

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

This post-Ottoman era church in Athens was built by locals to serve the residents of Anafiotica

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

The only surviving choragic monument is a trophy awarded in 334 BC for the winning dramatic chorus.

A Byzantine church containing the holy remnants of three saints sits atop the site of an ancient temple.

Where commuters walk through remnants of an ancient Greek necropolis.

A two thousand year old brothel uncovered in Northern Greece.

One of the most photographed locations in the entire city.

In a long-dry lake bed, these groups of massive stone pillars bear a striking resemblance to clumps of everyone's favorite fungi.

An ancient Thracian city where fire rituals were practiced on the largest cult altar in Southeast Europe.

This tower is all that remains of the mosque that once stood in the center of the city, before it was destroyed by fire in 1941.

This ancient structure appears Roman, but was constructed during the 16th century and was utilized until 1911.

A decaying, yet still functioning, work of communist architecture.

Rebuilt several decades ago, its striking murals prevent it from being reconsecrated as a church.

An homage to the medieval rulers of Bulgaria.

This massive concrete sculpture is said to be the heaviest communist monument on Earth.