It is very easy to walk by the unassuming entrance to Yerebatan Sarnayi, or the Basilica Cistern as it is often referred to.
Opposite the Aya Sofia, you’ll find a small building next to the tram line, with steps leading down into the cistern.
As you walk down into this 6th century Byzantine cistern you will be amazed at it’s size. Restored in 1980, this is the largest underground cistern in the city. It’s really a great hall, one hundred and forty metres long, seventy metres wide featuring 336 columns, each twelve metres high. It can hold an incredible eight thousand cubic meters of water. The columns are arranged in twelve rows of twenty eight columns, each supporting inticate brick vaulting. Some of the capitals are carved, others not.
It is thought that when Justinian 1 built this in 532 AD he had to demolish an old basilica and subsequently reused the capitals. At the time it was built it was used to store water for the Great Palace and other buildings in the area but later after the Ottoman revolt in 1453,  it was used to water the gardens of the Topkapi Palace.
tThe Basilica Cistern in Istanbul
 
The Basilica Cistern in Istanbul
The Basilica Cistern in Istanbul
 
Walk to the back of the cistern and you will find two Medusa heads supporting columns. The origin of these heads is unknown as is the reason that one was placed upside down and the other on its side.
The Medusa Heads at the Basilica Cistern in Istanbul
Another of Istanbul’s not to be missed sights!
 
 
Have you seen the Basilica Cistern in Istanbul?
 
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