Easily Istanbul's most photogenic building, the Blue Mosque (or the Sultan Ahmet Camii) was, as its formal name suggests, the grand project of Sultan Ahmet I (reigned 1603–1617), whose tomb is located on the north side of the site. Built partly on the site of the ancient Hippodrome of Constantinople, the mosque's wonderfully curvaceous exterior features a cascade of domes and six slender, fluted minarets. Beautifully crafted blue Iznik tiles adorn the interior and give the building its unofficial but commonly used name.
The architect, Sedefhar Mehmet Ağa, replicated with the mosque’s exterior the visual effect that the Hagia Sophia achieved with its interior. Its curves are truly voluptuous; it has six minarets (more than any other mosque at the time it was built), and its courtyard is the largest of all of the Ottoman mosques. The interior is on a similarly grand scale, mirroring perfectly the proportions of the outer courtyard: the Iznik tiles number in the tens of thousands, there are two hundred sixty windows in all, and the central prayer space is huge.