Lake Lacha Lake Lacha Lake Lacha () is a freshwater lake, located in the south of Kargopolsky District of Arkhangelsk Oblast in Russia, south of the town of Kargopol. It is the largest lake in Arkhangelsk Oblast, with a surface area of and a basin area of . Lake Lacha is the source of the Onega River, one of the major waterways of the White Sea basin. The etymological origin of the name is unclear. The river basin of Lake Lacha includes the southern and western parts of Kargopolsky District of Arkhangelsk Oblast, as well as north-west of Vologda Oblast. In particular,
Onega, Russia of Onezhsky District, even though it is not a part of it. As an administrative division, it is, together with three rural localities, incorporated separately as the town of oblast significance of Onega—an administrative unit with the status equal to that of the districts. As a municipal division, the town of oblast significance of Onega is incorporated within Onezhsky Municipal District as Onezhskoye Urban Settlement. The economy of the town is based on timber industry. There is also production of construction materials. Onega is a minor port on a bay on the White Sea, which routinely freezes in winter. The