Bordeaux wine regions all the producers within a given area: rather, only the producers (universally known as "châteaux", although not usually possessing the architectural grandeur that might imply) perceived as being of an unusually high standard are included in the classification. The châteaux included in the classification are referred to as "classed" or "classé", and those not included are referred to as "unclassed". Some classifications sub-divide the classed châteaux, according to the perceived quality. On the Left Bank, the Bordeaux Wine Official Classification of 1855 is the starting point for classification. Although this purports to be a classification of all Bordeaux wine, it
Bordeaux wine confluence of the Dordogne and Garonne Rivers, which flow into the Gironde. These rivers define the main geographical subdivisions of the region: In Bordeaux the concept of "terroir" plays a pivotal role in wine production with the top estates aiming to make "terroir" driven wines that reflect the place they are from, often from grapes collected from a single vineyard. The soil of Bordeaux is composed of gravel, sandy stone, and clay. The region's best vineyards are located on the well-drained gravel soils that are frequently found near the Gironde river. An old adage in Bordeaux is the best estates