Never converted to a mosque, Haghia Irene (Aya Irini), Justinian’s church of the Holy Peace in the first courtyard of The Topkapı Palace, was turned into an arsenal – hence the display of weaponry in its Ottoman dome painting. It stands on the site of a temple and the first Christian church in the city built by Constantine. Now a museum, the best way to experience it is to go to a concert (for listings and tickets, see www.biletix.com). Justinian’s 16th-century church was almost totally destroyed in the earthquake of 740 and was rebuilt in its present form after 753 by the most reviled of the iconoclast rulers, Constantine VII Kopronymos, so named because he allegedly defecated into his own baptismal font.