After the Ottoman conquest of Constantinople, Sultan Ahmed converted the city’s Christian church to a mosque, removing or plastering over Christian icons and adding minarets a mihrab and other elements characteristic of Muslim mosques. The mosque was then used as Istanbul’s primary place of prayer for several decades until the completion of the Blue Mosque.
After the Ottoman conquest of Constantinople, Sultan Ahmet Camii became and still is the city’s principal mosque and is the center of Islamic faith in the region. It’s English name, the Blue Mosque, derives of the intricate ceramic tiles on the interior walls of the mosque. The mosque is closed to the general public only during the periods of Islamic prayer.