房山区
From 1949 to 1958, the city steadily acquired land from neighboring Hebei Province. The last major additions occurred in 1958 with the incorporation of nine counties: Tong County (now Tongzhou District), Shunyi, Daxing, Liangxiang (now part of Fangshan District), Fangshan, Pinggu, Miyun, Huairou and Yanqing, adding for a total of . In 1958, the municipal population reached 6,318,497, of which 31.5% resided in the walled city, 29% in the immediate suburbs and the remainder in outlying towns and rural areas. City planners set a target population of 10 million for Beijing.