This river is located in the Kelduhverfi County and is renowned for its large sea trout and special ecology.  It discharges Lake Skjalftavatn, which was created during an earthquake period in 1974.

Hot and warm springs in the river bed and the surroundings elevate the water temperature to 10-12°C, which increases the growth of the trout and makes the variety of other flora and fauna greater than in most other such areas.  Salmon and sea char are also caught in the river and lake.