Lower Yenisei
The Great Kaz joins the Yenisei 300 km (186 mi) downstream from Strelka. It is noteworthy for its connection to the Ob via Ob-Yenisei canal and Ket River. The river starts to widen, its bed being littered with islands as numerous rivers augment its flow, in particular 1,800 km (1,120 mi) Stony (Podkamennaya) Tunguska, and the 3,000 km (1,860 mi) Lower (Nizhnyaya) Tunguska at Turukhansk draining the desolate central Siberian Plateau from the east. The remote Tunguska (Тунгуска) region is most famous for the 1908 meteorite impact, but is now being explored for oil. Beyond Turukhansk, the river enters tundra territory.
The river is icebound for more than half the year, and if unchecked ice could dam the river causing major flooding. Explosives are used to keep the water flowing. The final town is Dudinka which is connected to Krasnoyarsk by regular passenger boat. The river widens to a 50 km (31 mi) estuary, the Yenisei Gulf, for its final 250 km (155 mi) and the shipping lanes are kept open by icebreaker.
During the ice age, the route to the Arctic was blocked by ice. Though the exact details are unclear, the Yenisei is believed to have flowed into a huge lake filling much of western Siberia, eventually flowing into the Black Sea. (See West Siberian Glacial Lake of the early Weichselian Glaciation)
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