Libournais

The wine regions of Bordeaux are a large number of wine growing areas, differing widely in size and sometimes overlapping, which lie within the overarching wine region of Bordeaux, centred on the city of Bordeaux and covering the whole area of the Gironde department of Aquitaine.

The Bordeaux region is naturally divided by the Gironde Estuary into a Left Bank area which includes the Médoc and Graves and a Right Bank area which includes the Libournais, Bourg and Blaye. The Médoc is itself divided into Haut-Médoc (the upstream or southern portion) and Bas-Médoc (the downstream or northern portion, often referred to simply as "Médoc").

There are various sub-regions within the Haut-Médoc, including St-Estèphe, Pauillac, St.-Julien and Margaux and the less well known areas of AOC Moulis and Listrac. Graves includes the sub-regions of Pessac-Léognan and Sauternes (among others), and Sauternes in turn includes the sub-region of Barsac. The Libournais includes the sub-regions of Saint-Émilion and Pomerol (among others). There is an additional wine region of Entre-Deux-Mers, so called because it lies between the Garonne and Dordogne rivers, which combine to form the Gironde. This region contains several less well known sweet wine areas of Cadillac and St. Croix de Mont.

All of these regions (except the Libournais) have their own appellation and are governed by Appellation d'origine contrôlée laws which dictate the permissible grape varieties, alcohol level, methods of pruning and picking, density of planting and appropriate yields as well as various winemaking techniques. Bordeaux wine labels will usually include the region on the front if all the grapes have been harvested in a specific region and the wine otherwise complies with the AOC requirements. There are about 50 AOCs applicable to the Bordeaux region.

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Wikipedia