The Khorgo-Terkh national park is located in Tariat sum, Arkhangai province. Khorgo is a volcano, which exploded 8000 years ago. The volcanic crater lies at 2210m above sea level. The legend says in the past, some brave men would murder the corrupted aristocrats and help poor people by sharing. These men used to hide in this crater. Thus, the crater was given the name Khorgo, meaning to hide or sneak. The depth of the crater is around 90m, while its diameter is around 200-250m. Terkhiin Tsagaan nuur (or the great white lake) is a fresh water lake about 16km long, 20m deep and 5 km wide. The lake is 2100m above sea level. There are about ten rivers flowing into the lake, yet only one river flowing out, the Suman River. Khorgo-Terkh national park is a popular place for swimming, hiking, boating, and horse riding.