Constantinople's water supply was brought in via aqueduct, which meant it was vulnerable to enemy attack. So, Emperor Justinian built this massive Underground Cistern (and others like it) as a hedge against a long siege.
When the Ottomans took over, the cistern fell out of use and was forgotten. Centuries later, people started questioning why you could sink a well anywhere in this area and find an endless supply of fresh water. And even go fishing! After a bit of exploration, they re-discovered the Underground Cistern.
The entrance to the Underground Cistern is across the street from Aya Sofya.
When the Ottomans took over, the cistern fell out of use and was forgotten. Centuries later, people started questioning why you could sink a well anywhere in this area and find an endless supply of fresh water. And even go fishing! After a bit of exploration, they re-discovered the Underground Cistern.
The entrance to the Underground Cistern is across the street from Aya Sofya.
Visitors once had to rent boats to explore the cistern. Today, they pump out all but about a foot of water and walkways take you through this underworld.
The dim light and the faint dripping sounds gave it an eerie sort of "Phantom of the Opera" feel.
Yup, those are fish.
The Byzantines used whatever columns were available to support the brick roof. Notice all the different styles of columns and capitals.
There's wild speculation about the meaning of the two "Medusa head" columns. One is on its side (shown here), and one is upside down. Some say they symbolized the destruction of the pagan religions. Or possibly they were an attempt to scare off evil spirits. Others say they were simply pieces of stone that were the right size to support the column above.