The Surselva encompasses the valley of the Vorderrhein and all its side valleys, from the source near the Oberalppass all the way down towards Reichenau (where the Vorderrhein joins the Hinterrhein to form the Rhine). The district ends before that confluence at the huge forest on the giant debris of Flims Rockslide that is responsible for the name of the region: The debris area lack of water and soil and were ever left as a big forest as it was useless for farming. This forest (romonsch: selva) is the border for "Sur-selva" (meaning "above the forest").
The Surselva is one of the few areas in Switzerland that is mainly Romansh-speaking (another notable valley being the Engadin, the valley of the Inn). There are a few German-speaking communities in the Surselva, two notable ones being Obersaxen and Vals, which were founded in the thirteenth century by the Walser.
Romansh is the predominant language in the district, most of which speak the Sursilvan dialect. There is a large German-speaking minority in Surselva, notably the Walser settlements of Obersaxen and Vals. However, the percentage of Romansh-speakers is on the decline. Traditional Romansh-speaking cities such as Ilanz are losing ground to German.