 Although heavily transformed during both the Byzantine and the Ottoman eras, it is one among the few churches in Istanbul still extant, whose foundation goes back to the sixth century.The building lies in the Istanbul district of Fatih, in the neighborhood of Kocamustafapaşa, along "Koca Mustafa Paşa Caddesi".It is placed inside the walled city, and not far from the church of Saint John of Stoudion, on the slopes of the seventh hill of Constantinople near the sea of Marmara.