Tianjin or Tientsin (both: tyänˈjĭnˈ) [key], city and independent municipality (2010 pop. 12,938,224), NE China. In E central Hebei prov., it is a politically independent unit (4,400 sq mi/11,399 sq km) administered directly by the central government. The third largest city in China, Tianjin is a port at the confluence of the Hai River (c.30 mi/50 km from its mouth) with the Grand Canal. Although the harbor is poor, Tianjin is a leading international port of China and the collection and distribution center for the N China plain. It is connected by rail with much of China. A subway is being constructed, and several miles of it are already in use. Tianjin is an important manufacturing center, with iron- and steelworks, textile mills (cotton, woolen, and hemp), machine shops, a chemical industry based on salt, flour mills and other food-processing establishments, paper mills, and plants making heavy machinery, automobiles, precision instruments, cement, fertilizer, rubber products, carpets, lubricants, computers and computer components, and telecommunications equipment. The city has been designated a special economic zone in order to increase foreign trade and investment. The banking and trade industries are vital to the economy. Strategically located on the overland route to Manchuria, Tianjin has been a frequent military objective since its rise to importance in the late 18th cent. Agreements exacted from China by the British and French in 1860 made Tianjin a treaty port and conceded parts of it for foreign settlements and garrisons. In the Boxer Uprising (1900) there was a joint foreign occupation, and the Europeans razed the walls. With the abolition of the last foreign concessions in 1946, Tianjin was completely restored to Chinese sovereignty. The city has an astronomical observatory and is the seat of Hebei Univ., Nankai Univ., Tianjin Univ., a medical college, and a music conservatory.