Bordeaux wines are produced within the cultural limits of the Gironde department. The terroirs of these Bordeaux wines are distinguished by their geographical location vis-à-vis the Garonne and Gironde. On the left bank of the Garonne and along the Gironde, alluviums dominate the vineyard. They are essentially pebbles and gravel rolled from the Pyrenees where the river has its source 600 km upstream. These sand bass are well-drained terraces, warm and perfect for vines and cabernet sauvignon especially in Medoc and Pessac Léognan, where the great wines of Bordeaux have their source. On the other side of the river, in Libournais the terroirs have a different origin, with coasts and clay-limestone hills and deeper soils, perfect for Merlot.
