Satluj river originates at west of Lake Rakshastal in _______.
The Sutlej is sometimes known as the Red River. It is the easternmost tributary of the Indus River. Its source is Lake Rakshastal in Tibet. From there, under the Tibetan name Langqên Zangbo (Elephant River), it flows at first west-northwest for about 260 km to the Shipki La pass, entering India in Himachal Pradesh state.