The Church of the Holy Apostles (Greek: Ἅγιοι Ἀπόστολοι, Agioi Apostoloi; Turkish: Havariyyun), also known as the Imperial Polyándreion (imperial cemetery), was an Eastern Orthodox church in Constantinople, capital of the Eastern Roman Empire. The first structure dates to the 4th century, though future emperors would add to and improve on the space. It was second in size and importance only to the Hagia Sophia among the great churches of the capital. When Constantinople fell to the Ottomans in 1453, the Holy Apostles briefly became the seat of the Ecumenical Patriarch of the Greek Orthodox Church. Three years later the edifice, which was in a dilapidated state, was abandoned by the Patriarch, and in 1461 it was demolished by the Ottomans to make way for the Fatih Mosque.