Château Cos d'Estournel was built at the beginning of the 19th century by Louis Gaspard d'Estournel. Nicknamed the Maharadjah of Saint Estèphe on account of his passion for travel to the Indies, he built exotic pagodas above the winery, in memory of the distant lands he had visited. The property's wine quickly gained a reputation as one of Bordeaux's finest and began to be exported all over the world; in the 1855 classification it was ranked as a second growth. Today, this prestigious vineyard belongs to Michel Reybier and covers 67 hectares. With the Gironde estuary to the east and the Atlantic Ocean to the west, the property benefits from a microclimate with very stable temperatures. In old Gascon, Cos means hill of pebbles, which is certainly justified by the terroir's geological characteristics: an accumulation of gravel from the Quaternary era resulted in the formation of a hill about 20 metres high, on top of which sits the château, looking down over the river. Only grapes from vines that are more than 20 years-old are used to make Cos d'Estournel's grand vin, the rest go into the second wine. Carrying out nearly all tasks manually, the property uses new oak barrels to age the wines, thereby enhancing the flavours with a subtle woodiness. There is then a final selection, which reduces production to between 200,000 and 380,000 bottles.

An archetypal elegant, virile wine, Cos d'Estournel reveals a powerful fruitiness and superb body when it is still quite young, and then gradually evolves towards a superb aromatic complexity. A high proportion of Merlot makes the wine rich and supple; its potential to age can exceed a century in great vintages.