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

An abandoned Byzantine fortress and notorious prison.

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

Large collection from the 3rd millennium BCE.

The oldest cemetery of modern-day Athens blends the modern and ancient worlds.

An autonomous republic of Orthodox monks.

Hideout of thieves, monks, and goat-footed gods.

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

The ruins of an abandoned medieval city where the last Byzantine emperor was crowned.

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

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

This legendary city has been a tourist attraction for centuries.

The hallucinogenic center of the ancient world.

Monasteries on rock pillars, once accessible only by frayed ropes.

An underground network of massive stone arches and their skylit vaults support ruins of portico structures above.

Climb a set of vertiginous stone steps to the top of this impressive ancient edifice.

This crumbling medieval basilica once attracted pilgrims by the thousands to collect a miraculous dust that formed above the saint's tomb.

Carvings in Turkey's Marble Road may have directed ancient Romans to a hidden brothel.

Seven early Christians were sealed into a cave where legend has it they slept unharmed for centuries.

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

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

A fountain standing as a testament to a doomed alliance.

The alleged house of the Virgin Mary is tucked away in a park and nature preserve on Mt. Koressos in Turkey and is holy to both Catholics and Muslims alike.

The ancient abodes are a testament to human ingenuity amid harsh climates.