The Sauerland (ˈzaʊɐlant) is a rural, hilly area spreading across most of the south-eastern part of North Rhine-Westphalia, in parts heavily forested and, apart from the major valleys, sparsely inhabited.
The Sauerland is the largest tourist region in North Rhine-Westphalia, in particular for mountain biking and cycling, water sports and scenic recreation. The town and Skiliftkarussell of Winterberg in the Hochsauerlandkreis is a major winter sport resort.
The name Sauerland is first mentioned as Suderland in an official document from 1266. After 1400 the letter 'd' started to disappear. Therefore, Sauerland = southern country is the most convincing meaning, opposed to the theory that Sauer is from the German word sauer meaning sour (poor "sour" soil). Linguistically, "suder-“ is similar to the Old Saxon sûðar (southbound).
Before 1800 the western part of the Sauerland was part of the County of the Mark based in Altena; the eastern part adhered to the County of Arnsberg, later became known as the Duchy of Westphalia and was owned by the Archbishops and Electorate of Cologne. The Duchy of Limburg covered a very small area in the lower Lenne river valley. After the Napoleonic Wars the area became part of Prussia and was integrated into the new province of Westphalia. After World War II, Westphalia was merged with the new federal state of North Rhine-Westphalia. Today, the Sauerland consists of the districts Märkischer Kreis, Olpe and Hochsauerland. The western part of the Hessian district Waldeck-Frankenberg is also attributed to the Sauerland because of its geomorphological, as well as its sociocultural similarity, and the stark contrast to the rest of the adjoining Hessian landscape.
To the west the hills continue into the Bergisches Land, to the south into the Siegerland, and to the north-east into the Teutoburg Forest. The major rivers of the Sauerland are the Ruhr and the Lenne. Several artificial lakes were created on the smaller rivers by building dams to store water for the nearby Ruhr area, the biggest reservoirs being the Möhne and Bigge.