Yenisey

One of the main rivers in Russia, rising in the Sayan Mountains in the Asian Tuva region and flowing generally north through the Central Siberian Plateau into the Arctic Ocean; length 4,100 km/2,550 mi. The Yenisey has a drainage basin of 2,580,000 sq km/996,000 sq mi, and most of this area is at a height of between 487 m/1,600 ft to 700 m/2,300 ft above sea level. The Angara, the principal tributary of the Yenisey, helps to keep the river flow even because of its constant source of water in Lake Baikal. Navigable throughout almost its entire course, the Yenisey's chief ports are Dudinka, Igarka, and Krasnoyarsk.