St. Irene, which is located on 1st courtyard of Topkap� Palace, was constructed by the Emperor Lustiniaus in VI. century. It consists of atrium, narthex, naos with three nephs and apse. It is a typical Byzantine structure with its material and architecture. There have not been many changes in the building, as the church was not turned to a mosque after conquest of �stanbul in 1453. It was used as a booty and weapon warehouse for a long time.