A 75 kilometre long and 5 to 15 kilometre wide estuary in southwest France. It is formed by the confluence of the two rivers Dordogne and Garonne and then flows into the Atlantic. With a surface area of 685 km², the Gironde is the largest estuary in Europe. The Gironde begins at the pointed Bec d'Ambes peninsula formed by the two rivers, about 15 kilometres north of the city of Bordeaux. The entire length of the left bank is covered by the Médoc wine-growing area, which is ideally suited for viticulture due to the permeability of the gravel and pebble soil. The best crus (sites) are those that "see the water" (bordering the Gironde), because the sunlight is reflected by the large surface of the water. The retention of heat results in very good conditions for optimal grape ripening. The six famous communal appellations of the Haut-Médoc are located here.