Lanzhou is a prefecture-level city and capital of Gansu province in northwestern China.Lanzhou was badly damaged during the rising of the Gansu Muslims in 1864–1875. In the 1920s and 1930s it became a center of Soviet influence in northwestern China. During the Sino-Japanese War (1937–1945) Lanzhou, linked with Xi'an by highway in 1935, became the terminus of the 3,200 km (2,000 mile) Chinese-Soviet highway, used as a route for Soviet supplies destined for the Xi'an area.