Basilica Cistern

The Basilica Cistern, also known as the "Sunken Palace" or "Yerebatan sarayi", is the largest of several hundred ancient cisterns that lie beneath the city of Istanbul (formerly Constantinople), Turkey. The cistern, located 500 feet (150 m) west of the Hagia Sophia on the historical peninsula of Sarayburnu, was built in the 6th century during the reign of Byzantine Emperor Justinian I. It was constructed to supply water to the Byzantine Palace primarily.

Basilica cistern is a very authentic place and a must see in Istanbul. It is open every day from 09:00 hrs to 18:30 and the entrance fee is 10 YTL (~7 USD) for foreign visitors.


Walk to the back of the Basilica Cistern, and you will find one upside down Medusa head supporting one of the columns. Why it is upside down has been a question of much discussion, but the best guess is that the people who placed the stone believed that if the head was upside down, it would ward off evil spirits. Not far from the upside-down Medusa head is a second Medusa head, which is sideways. Why one head is upside down and the other is sideways only deepens the question about their orientation.

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