They have a westerly course, but after uniting they turn N, through the Sayan Mountains in the wild gorge of Kemchik, in 92° E. Thence the river makes its way across the Alpine region that borders the Sayan Mountains on the N until it emerges upon the steppes at Sayansk (53° 10' N).
Augmented by the Abakan on the left and the Tuba on the right, it traverses the mining region of Minusinsk, approaches within 6 m. of the Chulyni, a tributary of the Ob, intersects the Trans-Siberian railway at Krasnoyarsk, and is joined first by the Kan and then by the Upper (Verkhnyaya), the Stony (Podkamennaya), and the Lower (Nizhnyaya) Tunguska, all from the right.
The Upper Tunguska, known also as the Angara, drains Lake Baikal, and is navigable from Irkutsk. The Yenisei continues N to the Arctic Ocean, joined on the left by the Zym, Turukhan and Ingarevka, and on the right by the Kureika and Daneshkina.
After the confluence of the Angara, the stream continues to widen out to 30 m., its bed being littered with islands until it breaks into its delta (240 m. long). The length of the river is 4093 km (2543 m.), and the area of its drainage basin 970,000 sq. m. It is navigable as far up as Minusinsk, a distance of 2900 km (1840 m.), and is free from ice on the average for 155 days at Turukhansk and for 196 days between May and November at Krasnoyarsk.
A canal connects the Great Kaz, a tributary of the Yenisei, with the Ket, an affluent of the Ob.