Hagia Irene, which stands on the first base-court of Topkapı Palace, was built in the time of Emperor Justinian in the 6th century. It is a typical Byzantine construction with its materials and architecture. It is the unique church with an atrium that has survived until today in Istanbul. After the conquest of Istanbul in 1453, no big change was made in the building since it was not transformed into a mosque. Hagia Irene, which is one of the first churches of Byzantine, reflects all the architectural aspects of the period of Justinian I. Hagia Irene, which was named as Müze-i Hümayun (the Imperial Museum) in 1869 after being used as booty storage and armory for a long time and has been used as a military museum since 1908, is also used for concerts and performances through being reserved for various events, particularly festivals.