Western Siberian Plain

The West Siberian Plain, also known as Zapadno-sibirskaya Ravnina, (Russian: За́падно-Сиби́рская равни́на) is a large plain that occupies the western portion of Siberia, between the Ural Mountains in the west and the Yenisei River in the east, and by the Altay Mountains on the southeast. Much of the plain is poorly drained and consists of some of the world's largest swamps and floodplains. Important cities include Omsk, Novosibirsk, Tomsk and Chelyabinsk.

The West Siberian Plain is located east of Ural Mountains mostly in the territory of Russia. It has been described as the world's largest unbroken lowland—more than 50 percent is less than 100 metres (330 ft) above sea level—and covers an area of about 2.6–2.7 million square kilometres (1.0 million square miles) which is about one third of Siberia, extending from north to south for 2,400 km (1,490 mi), from the Arctic Ocean to the foothills of the Altay Mountains, and from east to west for 1,900 km (1,180 mi) from the Ural Mountains to the Yenisei River.

The plain has eight distinct vegetation regions: tundra, forest-tundra, northern taiga, middle taiga, southern taiga, sub-taiga forest, forest-steppe, and steppe. The number of animal species in the West Siberian Plain ranges from at least 107 in the tundra to 278 or more in the forest-steppe region. The long Yenisei river flows broadly south to north, a distance of 3,530 km (2,195 mi) to the Arctic Ocean, where it discharges more than 20 million litres (5 million gallons) of water per second at its mouth. Together with its tributary Angara, the two rivers flow 5,530 km (3,435 mi). The valley formed by the Yenisei acts as a rough dividing line between the West Siberian Plain and the Central Siberian Plateau. Glacial deposits extend as far south as the Ob-Irtysh confluence, forming occasional low hills and ridges, but otherwise the plain is exceedingly flat and featureless.

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