Blue Mosque or The Sultan Ahmed Mosque is an historic mosque in Istanbul. The mosque is popularly known as the Blue Mosque for the blue tiles adorning the walls of its interior. It was built during the rule of Ahmed I.
Map of Constantinople (modern Istanbul), by Florentine cartographer Cristoforo Buondelmonti. The oldest surviving map of the city, and the only surviving map which predates the Turkish conquest of Constantinople in
sectional view of the Hagia Sophia -hellenic Byzantium and now Istanbul, Turkey - showing how the pendentives and semi-domes support the central dome built architects: Anthemios of Tralles, Isidorus of Miletus