Black Forest, mountain region, Baden-Württemberg Land (state), southwestern Germany, source of the Danube and Neckar rivers. It occupies an area of 2,320 square miles (6,009 square km) and extends toward the northeast for about 100 miles (160 km) from Säckingen on the Upper Rhine River (at the Swiss border) to Durlach (east of Karlsruhe). Its width varies from 10 to 25 miles. Structurally and topographically, it forms the counterpart of the Vosges, which lies west of the Rhine valley. The Black Forest drops abruptly to the Rhine plain but slopes more gently toward the Neckar and Nagold valleys to the east.
It is mainly a granite highland with rounded summits, although its northern part comprises forested sandstone, and it is bordered to the south by a narrow band of lower and more fertile limestone. Divided into two parts by the deep Kinzig valley, its highest summits—Feldberg (4,897 feet [1,493 metres]), Herzogenhorn, and Blössling—are to the south. Its northern half has an average height of 2,000 feet.
The raw climate of the higher districts supports only hardy grains, but the valleys are mild with good pastureland. Oak and beech woods clothe the lower slopes, while the extensive fir forests, which gave the range its name, climb to 4,000 feet. Traditional economic activities—such as lumbering, woodworking, and the manufacture of watches, clocks, and musical instruments—continue. Newer manufactures include electronic equipment and precision machinery. Tourism and winter sports are also prominent, and there are many mineral springs and spas, such as Baden-Baden and Wildbad. Principal cities are Freiburg im Breisgau, Offenburg, Rastatt, and Lahr.