The Yenisey or Yenisei (/ˌjɛnɪˈseɪ/ YEN-iss-AY; Russian: Енисе́й, pronounced [jɪnʲɪˈsʲej]) is the fifth-longest river system in the world, and the largest to drain into the Arctic Ocean.
Rising in Mungaragiyn-gol in Mongolia, it follows a northerly course through Lake Baikal and the Krasnoyarsk Dam before draining into the Yenisey Gulf in the Kara Sea. The Yenisey divides the Western Siberian Plain in the west from the Central Siberian Plateau to the east; it drains a large part of central Siberia. Its delta is formed between the Gyda Peninsula and the Taymyr Peninsula.