Chirkuo
The Chirkuo is a river in Yakutia, Russia. It is a right hand tributary of the Vilyuy, and is long — including the Duikhta at its head, with a drainage basin of.
In the Ust-Chirkuo Site there are remains of ancient settlements by the river. Currently there are no permanent inhabited places in the river area.
Course
The Chirkuo lies in the upper stretch of the Vilyuy basin. It begins at the confluence of the Duikhta and the Kucchuchi-Chuurka in the Vilyuy Plateau. The river flows roughly northwards across the plateau along the border with Irkutsk Oblast to the west. Finally it meets the right bank of the Vilyuy from its mouth in the Lena. The river freezes between mid October and late May.The main tributaries of the Chirkuo are the long Golusakh and the long Dulisma from the left. The last stretch and mouth area of the Chirkuo are part of the backwater of the Vilyuy Reservoir.