Khudan
Khudan takes its name from a river of the uplands east of Lake Baikal. The Khudan rises near the junction of the Khudan and Tsagan-Khurtei ranges, not far from the mountain that shares its name. Flowing generally west-northwest, it joins the Uda, whose waters in turn reach the Selenga. The river's long winter freeze typically lasts from autumn until April or May.