The Koshi or Kosi River (Nepali: कोशी नदी, koshī nadī कोसी नदी, kosī nadī) drains the northern slopes of the Himalayas in the Tibet Autonomous Region and the southern slopes in Nepal. From a major confluence of tributaries north of the Chatra Gorge onwards, the Koshi River is also known as Saptakoshi (Nepali: सप्तकोशी, saptakoshī) for its seven upper tributaries.