The largest and most imposing of Istanbul's mosques built by the Ottomans is the Suleymaniye Mosque, commissioned by Sultan Suleyman the Magnificent and opened in 1557. The mosque sits high on a hill with a commanding view of the Golden Horn and beyond. Süleyman's reign spanned 47 years (1520-1566, the longest reign of any Ottoman sultan), brought the empire to the height of its powers, and was a golden age in learning and the arts, including architecture. The Süleymaniye Mosque was designed by the prolific Ottoman architect Mirmar Sinan (1489-1588) and represented Süleyman's and Sinan's response to the Byzantines' great Aya Sophia. (Sinan, who lived to be 90 and was active to the last, not only built hundreds of buildings in present-day Turkey and established a model of Ottoman architecture that would endure for centuries to come, but built structures in surprisingly far flung places like Višegrad in modern Bosnia and Yevpatoria on the Crimean Peninsula.) Imposing as it is, however, the Suleymaniye Mosque is still somewhat smaller, with a smaller and lower dome, than the Aya Sophia built 1000 years before.
As a mosque endowed by the sultan, the Suleymaniye was entitled to (and has) four minarets, the maximum then considered allowable (though Sultan Ahmet was to later break with tradition; see below). Mosques commissioned by other high-ranking members of the royal family were entitled to two minarets, while all other mosques were limited to one. When it was built, and for centuries thereafter, the mosque was part of a large complex that served not only as a place of worship but as a charitable foundation and a place of public accommodation. The complex included a hospital, a public kitchen said to have served more than a 1000 people a day (Muslims, Christians and Jews alike), religious schools (madrasahs), baths, shops and a caravansary where travelers could find lodging for themselves and their animals. Süleyman himself, his favorite wife Roxelana, and other members of Ottoman royalty are buried in mausoleums on the grounds.