Hankou (hänˈkōˈ) [key] or Hankow hăngˈkouˈ, former city, since 1950 part of the Wuhan conurbation, E Hubei prov., China. Built on an alluvial plain on the left banks of both the Han and Chang rivers, it is the largest city in the conurbation and contains its port, a major facility handling oceangoing vessels. The city has many industries. Hankou owes much of its development to the Beijing-Guangzhou RR, which crosses the Chang at Hankou. The city was opened as a treaty port in 1862, held (1938–45) by the Japanese, and in 1949 passed to the Chinese Communists. It is linked by bridges with Hanyang and Wuchang.