The ruins of an ancient Zoroastrian Tower of Silence believed to be the earliest example of the traditional funerary practice.

These "50 Fortresses" have been unearthed in the ancient oasis of Khwarezm.

Once a bustling fishing port, this semi-ghost town is now more than 90 miles away from the shore.

Ancient barriers wrap around what was once an important stop along the Silk Road.

Scars of this building's past life as a violent prison still cover its walls.

There are many Byzantine-era churches still standing in Athens, but this is the only one with a 2,500-year-old column rising through its roof.

Elaborate stone houses constructed from the ruins of war.

The home of Greece’s national poet sits crumbling in the middle of a popular tourist district.

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

The ruins of an ancient mansion sits in front of and underneath a contemporary art gallery.

This Ottoman-era church is hidden amid a busy tourist area.

These ancient ruins hide in plain sight next to a dessert shop.

The ruined doorway is a portal to the building's turbulent and torturous past.

This historic structure has been used as a mosque, a barracks, a prison, a school, and a bakery.

Legend says it was constructed with the destroyed pillar of an ancient Greek Temple.

A crushed gate and giant bronze head serve as a reminder of Greece's fight for freedom.

A tiny Greek Orthodox church from the Ottoman era hides on a busy city street.

According to legend, this ancient column contains healing properties.

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

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

A unique housing complex born from the aftermath of the Greek Civil War.

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

These caves secretly held national treasures during World War II.

This graffitied 19th-century building was a prototype of European industrial architecture.