The Hagia Irene or “Holy Peace” basilica, located right by Hagia Sophia, was an Orthodox church that is now a museum and a performance hall. The 6th century Byzantine structure is often referenced as the first church to be built in Constantinople, commissioned by Constantine I and later restored to its present form by Justinian I. It was incorporated into the Topkapı Palace complex by the Ottomans, who used it as an armory and warehouse.
