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Over 2 million people visited the Basilica Cistern last year

The Basilica Cistern known as the Yerebatan Sarayı in Turkish (Sunken Palace) was visited by over 2 million people last year according to the Turkish Travel Agencies Union (TÜRSAB).

The Basilica Cistern was built in 542 by the Byzantine Emperor Justinian I to provide water to the ‘Great Palace of Constantinople’. The Ottomans also used the Basilica Cistern following the conquest of Istanbul to provide water to Topkapi Palace.

1.7 million of the 2.1 million visitors were tourists from abroad, making it the most highly visited historical attraction by foreign visitors in Istanbul.