The Sultanahmet Mosque, known as the Blue Mosque, is the central element of the complex built by Ahmed I (1603-1617) and was completed after the sultan's death in 1617. Its architect is Mehmed Aga (d.1622), whose epithet "Sedefkar" refers to his mastery in mother-of-pearl. The mosque is considered to be the last example of Ottoman classical architecture; Mehmed Aga was an apprentice under Sinan (1450?-1588) and Davud Aga (d.1598), two architects whose works have defined the style of this period.
The mosque is composed of a large prayer hall unified under a single dome and an open courtyard to the northwest. It is oriented thirty-nine degrees east of south. An outer precinct, enclosed by a stonewall with windows, wraps around the mosque and court on all sides except for qibla. The elevation drops sharply towards the Bosphorus on the qibla wall side where a separate terrace and a royal kiosk were built on a partial basement.
Istanbul (historically Byzantium and later Constantinople; see the other names of Istanbul) is the largest city of Turkey and the third largest city in the world. The city covers 27 districts of the Istanbul province.It is located on the Bosphorus Strait and encompasses the natural harbor known as the Golden Horn, in the northwest of the country. It extends both on the European (Thrace) and on the Asian (Anatolia) side of the Bosphorus, and is thereby the only metropolis in the world which is situated on two continents. In its long history, Istanbul served as the capital city of the Roman Empire (330–395), the East Roman (Byzantine) Empire (395–1204 and 1261–1453), the Latin Empire (1204–1261), and the Ottoman Empire (1453–1922). The city was chosen as joint European Capital of Culture for 2010. The historic areas of Istanbul were added to the UNESCO World Heritage List in 1985.