Khövsgöl Province in the context of Buryatia

Lake Khövsgöl (Mongolian: Хөвсгөл нуур), also referred to as Khövsgöl Sea (Хөвсгөл далай), is a lake in Khövsgöl Province, Mongolia. It is the largest freshwater lake in the country by volume, and the second largest by area after Uvs Lake. It is nicknamed "Mother Sea" (Далай ээж, Dalai eej) in Mongolian.

Uvs Lake Basin (also Uvs Nuur Basin or Ubs Nuur Basin; Mongolian: Увс нуурын хотгор, romanized: Uws nuuriin hotgor) is an endorheic basin located on the territorial border of Mongolia and Tuva, a republic of the Russian Federation. The basin is part of the Central Asian Internal Drainage Basin and is named after Uvs Lake (Uvs Nuur, Ubsu Nur), a large saline lake situated in the western part of its drainage basin, and is one of the last remnants of the mammoth steppes. Uvs Lake is a shallow lake with an area of 3,350 km (1,290 sq mi). Its entire basin, which includes several smaller lakes, is 70,000 km (27,000 sq mi).

Uvs Lake Basin may also refer to Ubsunur Hollow (Russian: Убсунурская котловина, Ubsunorskaya Kotlovina), which is the western part of the drainage basin, or to over 10,000 km (3,900 sq mi) of protected areas covering the lake and its surroundings. The hollow forms the northern part of the Great Lakes Depression, which has a surface of over 100,000 km (39,000 sq mi). The hollow, and most of the drainage basin, are situated in the Khövsgöl, Zavkhan and Uvs Provinces of north-western Mongolia, and the Mongun-Tayginsky, Ovyursky, Tes-Khemsky and Erzinsky Districts of southern Tuva.