Ögii Lake is a freshwater lake, 7.9 km long, 5 km wide located in eastern Arkhangai, in central Mongolia. The lake, designated as a Ramsar Site of International Importance, is known for its fish and for birdlife. It is a stopover point for migrating waterbirds of the family Anatidae. Almost half the lake is less than 3 meters (10 ft) deep. .