The Tüllinger Berg (lit. German: Tüllinger mountain) short form Tüllinger, also known as Tüllinger Hügel in Switzerland , is a partly forested mountain located at an elevation of 460.2 m above sea level. It is situated in the southwest of Baden-Württemberg, at the border triangle of Germany, France, and Switzerland. The mountain extends about two kilometers from east to west and about five kilometers from north to south, forming a natural border between the urban areas of Lörrach and Weil am Rhein . Notably, the Tüllinger Berg is characterized by the break-off edge of the high strand of the Rhine Valley and the meadow floodplain. The slope of the Tüllinger Berg, especially with its western mountain nose, defines the surrounding landscape.