The commune of Saint-Estèphe is the most northerly of the Médoc on Bordeaux's left bank. Its vineyards lie close to the mighty Gironde, which serves to temper the climate here, which tends to be cooler than the communes to the south. Château Cos Labory is situated to the south of the commune, close to the border with Pauillac. The estate covers eighteen hectares, planted 60% cabernet sauvignon, 35% merlot, 5% cabernet franc on gunzian gravels.
The name of the property comes from a particular lieu-dit (vineyard plot) called Caux, which means hill of gravel and from the owner from 1820-1840, Monsieur François Labory. The estate was sold in 1845 to Monsieur d'Estournel, and again in 1852 to an English banker, Charles Martyns. It has now been owned by the Audoy family for over half a century.
Classified a fifth growth in the 1855 Classification of the wines of Bordeaux, the property has tended to underperform alongside its celebrated neighbours, but its wines occasionally shine.