At Topkapı Palace, the Harem Apartments were where the sultans lived together with their families. Reflecting architectural styles ranging from the 16th century to the early 19th century, the entire complex is of the greatest importance in terms of architectural history. The Harem was initially established within the Second Courtyard above the palace’s back gardens and expanded greatly over the centuries. The apartments were secluded with great care by means of high walls, from the more public courtyards and sections of the palace where government business was conducted. Soon after Topkapı Palace was constructed, the Old Palace (located in the Bayezid neighborhood of Istanbul) began to be used solely as the harem, while Topkapı Palace became the seat of government and of public functions (which together were called “selamlık”). However, there are also some sources stating that, during this same period, a small harem, the Girls’ Palace (Sarây-ı Duhterân), was also built beside the palace’s Golden Road. The Harem developed in four stages, with perhaps the most intense period of construction and organization occurring when Sultan Suleiman the Magnificent (r. 1520-66) moved into the Topkapı Palace harem together with his Haseki (“favorite”) Hürrem Sultan (known as Roxelana in the West) and his family; this period continued until the 18th century. The Harem contains more than 300 rooms, nine bathhouses, two mosques, a hospital, dormitories, and a laundry. The basic plan of the Harem consists of consecutive courtyards surrounded by and interspersed with living quarters, rooms, pavilions, and service buildings.