The wine-growing region is located in the federal state of Baden-Württemberg in Germany. The vineyards cover 11,461 hectares of vines, stretching between Lake Con stance and the valley of the Tauber below Rothenburg (Taubergrund). The geographical and climatic conditions are shaped by many river valleys. On its very winding course, the tributaries Rems, Enz, Kocher and Jagst flow to the Neckar. On the riverbanks are many south-facing slopes with widely spaced vineyards. In summer there is enough sun to give red wines strength and colour. Two thirds of the vineyards are steep slopes or hillside sites. Heilbronn is the wine capital of Württemberg and, to a certain extent, of Germany, because the DLG (German Agricultural Society) competition is held here every year. Weinsberg is home to a teaching and research institute for vine breeding, where August Herold (1902-1973) created several successful new varieties such as Dornfelder, Cabernet Cubin, Cabernet Dorio and Cabernet Dorsa.