The river rises in the Spanish Pyrenees (and is called Garona there), crosses the border after France and then flows northwest there. Below the city Bordeaux it unites with the river Dordogne and forms the large mouth funnel Gironde that flows into the Atlantic. Already in Roman times the Garonne was an important traffic route through the province of Gaul for the Wine trade. There are many appellations along the banks of these waters, for example Barsac, Cadillac - Cotes de Bordeaux, Cerons, Sauternes, Graves, Premières Cotes de Bordeaux and the as Haut-Médoc designated southern part of Médoc.
Three departments along the river are Haute-Garonne, Tarn-et-Garonne and Lot-et-Garonne, the latter two named after the Garonne tributaries Lot and Tarne. The large area between the rivers Garonne and Dordogne is called Entre-deux-Mers with many appellations. The left bank along the Garonne and the Gironde estuary is called Rive gauche designated. See also under Skin pays.