The German Central Uplands (Mittelgebirgsschwelle) is the Mittelgebirge area of low mountains and hills, comprising numerous individual ranges like the Rhenish Massif, the Lower Saxon Hills, the West and East Hesse Highlands, the Harz and the Thuringian-Franconian Highlands as well as the Bohemian Massif - in between the North German Plain and the Main river separating it from the South German Scarplands. The Thuringian Basin forms one of the core regions.