Chaun River – a river in the Chukotka Autonomous Okrug, Russia. The river runs for 205 km. It arises from the ridges of the Chukchi Plateau to the northwest of Lake Elgygytgyn. It runs through the Elgygytgyn Plain and then flows into the southern part of the Chaun Bay, near the East Siberian Sea, about 100 km from the town of Pevek. The delta is comprised of several branches up to 2 km in width and approx. 0.7 m in depth. After the flood, the riverbed migrates. In the high water, the river rises up to 3 m. Approximately 15 rivers and streams flow into the river.