The Lyutoga (Russian: Лю́тога) is a river on Sakhalin island, third by size within the island. It flows through Kholmsk and Aniva districts of Sakhalin Oblast. Starting at the western slope of the Mitsulsky Mountain Ridge, which belongs to the system of Western Sakhalin Mountains. It flows along a wide valley from North to South, and discharges into the Aniva Bay of the Sea of Okhotsk. There is a town of Aniva (Russian: Ани́ва) (with population of ca. 8,100 people) in the mouth of the river, the town used to have the same name as the river before 1905. There are several comparatively large villages located on Lyutoga banks (upstream to downstream): Pyatirechie (Russian: Пятире́чье) (ca. 600), Chaplanovo (Russian: Чапла́ново) (ca. 900), Ogon'ki (Russian: Огоньки́) (ca. 400) and Petropavlovs