The Anadyr (; Yukaghir: Онандырь; ) is a river in the far northeast of Siberia which flows into the Gulf of Anadyr of the Bering Sea and drains much of the interior of Chukotka Autonomous Okrug. Its basin corresponds to the Anadyrsky District of Chukotka. Geography The Anadyr is long and has a basin of . It is frozen from October to late May and has a maximum flow in June with the snowmelt. It is navigable in small boats for about to near Markovo. West of Markovo it is in the Anadyr Highlands (moderate mountains and valleys with a few trees) and east of Markovo it moves into the Anadyr Lowlands (very flat treeless tundra with lakes and bogs). The drop from Markovo to the sea is less than . It rises at about 67°N latitude and 171°E longitude in the Anadyr Highlands, near the headwaters of the Maly Anyuy, flows southwest receiving the waters of the rivers Yablon and Yeropol, turns east around the Shchuchy Range and passes Markvovo and the old site of Anadyrsk, turns north and east and receives the Mayn from the south, thereby encircling the Lebediny Zakaznik, turns northeast to receive the Belaya from the north in the Parapol-Belsky Lowlands, then past Ust-Belaya it turns southeast into the Anadyr Lowlands past the Ust-Tanyurer Zakaznik and receives the Tanyurer from the north. At Lake Krasnoye, it turns east and flows into the Onemen Bay of the Anadyr Estuary. If the Onemen Bay is considered part of the river, it also receives the Velikaya from the south and the Kanchalan from the north. Other important tributaries are the Yablon, Yeropol and Mamolina from the right and the Chineyveyem and Ubiyenka from the left. Its basin is surrounded by the Amguema and Palyavaam basins to the north, the Bolshoy Anyuy, Oloy and Kolyma basins to the northwest, and the Penzhina basin to the southwest. History In 1648, Semyon Dezhnev reached the mouth of the Anadyr after being shipwrecked on the coast. In 1649, he went upriver and built winter quarters at Anadyrsk. For the next 100 years, the Anadyr was the main route from the Arctic to the Pacific and Kamchatka. In the 18th century, the Anadyr was described by the polar explorer Dmitry Laptev. Ecology The country through which it passes is thinly populated, and is dominated by tundra, with a rich variety of plant life.