The Sanjiang Plain (Chinese: 三江平原; lit. 'three rivers plain') is a fluvial plain around the confluences among the Amur River, Songhua River and Ussuri River in Northeast Asia, encompassing about 109,000 km (42,000 sq mi) with extensive wetlands.. The plain is located within a basin east of the Lesser Khingan Range, south of the Bureya and Badzhal Ranges, west of the Sikhote-Alin, and north of the Wanda Mountains. The southwestern portion of the plain upstream of and between the courses of the Amur and Ussuri belongs to China, encompassing 23 counties of the Heilongjiang province; while the rest of the region belongs to the Jewish Autonomous Oblast and Khabarovsk Krai of Russia's Far Eastern Federal District.
