Toson Nuur is situated 5km from Delgerkhaan Soum of Khentii province. This carbonate-type salt lake with a sandy bottom stretches 300 meters long and 250 meters wide dimpled area. According to the local’s talk, people have been coming to the lake as a medical purpose for over 100 years. Aristocrats used to stay on south of the lake, monks on the north and commoners on the east and west. Northwest bank of the lake contains a light grey and a dark blue mud under the surface which have a clingy property. But a black greasy mud on south of the lake arises from 50cm below the surface.

The water comes from a hole in northwest corner of the lake. Containing light pack sand, this hole is 15m long, 7m wide and so deep that one may lose his or her footing. Several herds died in the hole and skeletons of them come out in yellow like rust.   The locals call the hole as Bumbaa. Water of the lake is tasteless, odorless, light green in color and contains many kinds of tiny animals, such as 1cm long leeches and little lady beetles. Mud of the lake is used for a traditional medicine during the syphilis, and mydriasis, tophus, high and low blood pressure, nervous breakdown, dermatitis, allergy, polyp and diabetes.