The Verkhovyansk Range is an L-shaped range that runs down the east side of the Lena before turning west-east across the south of the ecoregion. They Chersky Range runs northwest-to-southeast through the middles of the region. Their upper slopes and peaks are too cold and dry to support the forests and flora of the lowlands in the Northeast Siberian taiga ecoregion. To the east and north of the mountains is the Kolyma River basin. In addition to the Kolyma River, the ecoregion contains the Indigirka River and the Yana River.