Nen River

The Nen River or Nenjiang (Chinese: ; pinyin: Nèn Jiāng; Wade–Giles: Nen-chiang), or Nonni (Manchu: ᠨᠣᠨ
ᡠᠯᠠ; Möllendorff: Non ula; Abkai: Non ula) is a river in Northeast China. The Nen River flows through the northern part of Heilongjiang Province and the northeastern section of Inner Mongolia, some parts of the river forming the border between the two regions. At 1370 kilometres (850 mi) in length, the Nen River is the longest tributary of the Songhua River.

The Nen River flows in the general southern direction in a wide valley between the Greater Khingan and the Lesser Khingan mountain ranges in the west and east, respectively, and meets the Second Songhua River near Da'an to form the Songhua River .

The river is prone to flooding, as occurred most recently in 1998 and 2005.

Major tributaries of the Nen River include:

During the Qing Dynasty the Nenjiang provided an important communication route between southern Manchuria and the cities of Qiqihar and Mergen, both of which served at various points as capitals of the Qing Heilongjiang. A portage road connected the upper reaches of the Nenjiang with Aigun on the Amur as well.

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