Tianjin is the sixth largest city of the People's Republic of China in terms of urban population. Administratively it is one of the four municipalities that have provincial-level status, reporting directly to the central government. Also, its urban land area is the fifth largest in China, ranked only after Beijing, Shanghai, Guangzhou and Shenzhen.
Tianjin's urban area is located along the Hai He River, which connects to the Yellow and Yangtze Rivers via the Grand Canal in Tianjin. Its ports, some distance away, are located on Bohai Gulf in the Pacific Ocean. Tianjin was once home to foreign concessions in the late Qing Dynasty and early Kuomintang (KMT) era. The municipality now incorporates the coastal region of Tanggu, home to the Binhai and the Technology and Economic Developing Area (TEDA). Tianjin Municipality borders Hebei province to the north, south, and west; Chinese capital Beijing is to the northwest, and Bohai Gulf to the east.
Tianjin is at the northern end of the Grand Canal of China（大運(yùn)河）, which connects with the Yellow River （黃河） and Yangtze River （長江）.
Tianjin Municipality is generally flat, and swampy near the coast, but hilly in the far north, where the Yanshan Mountains （燕山） pass through the tip of northern Tianjin. The highest point in Tianjin is Jiushanding Peak on the northern border with Hebei, at an altitude of 1078 m.
The Hai He River （海河） forms within Tianjin Municipality at the confluence of the Ziya River（子牙河）, Daqing River（大清河）, Yongding River（永定河）, North Grand Canal, and South Grand Canal; and enters the Pacific Ocean at Tianjin Municipality as well, in Dagu District. Major reservoirs include the Beidagang Reservoir in the extreme south (in Dagang District) and the Yuqiao Reservoir in the extreme north (in Ji County).
The urban area of Tianjin is found in the south-central part of the Municipality. In addition to the main urban area of Tianjin proper, the coast along the Bohai is lined with a series of port towns, including Tanggu （塘沽） and Hangu（漢沽）.
Tianjin's climate is a monsoon-influenced humid continental climate (Koppen climate classification Dwa) characterized by hot, humid summers, due to the monsoon, and dry, cold winters, due to the Siberian anticyclone. Average highs in January and July are 2 °C (36 °F) and 31 °C (87 °F) respectively). Spring is windy but dry, and most of the precipitation takes place in July and August. Tianjin also experiences occasional spring sandstorms which blow in from the Gobi Desert and may last for several days.