The river starts near a small village Bun in the foothills of Patriata and Murree. It provides water to Simblee Dam, which is reservoir of water for Islamabad. Near Pharwala Fort it cuts through a high mountain range and that is a wonderful phenomenon of nature. The place is called Swan Cut. No stream can cut such a high mountain. It proves the Swaan was there before the formation of this range. And when the mountain rose through millions of years, the stream continued its path by cutting the rising mountain. Ling stream, following a relatively long course though Lehtrar and Kahuta falls in the Swaan near Sihala.