Champagne Michel Reybier Brut Premier Cru

Château Cos d'Estournel is a winery in the Saint-Estèphe appellation in the Bordeaux region of France. It is also the name of the red wine produced by this property. The wine produced here was classified as one of fifteen Deuxièmes Crus (Second Growths) in the original Bordeaux Wine Official Classification of 1855.

Château Cos d'Estournel produces the eponymous grand vin, the second wine since the 1994 vintage, Les Pagodes de Cos from the estate's younger vines, as well as Château Marbuzet from fruit from nearby plots. The property is adjacent to Château Lafite-Rothschild in the neighboring commune of Pauillac. The name Cos refers to a "mound of pebbles" in the Gascon dialect and the name Cos d'Estournel was given in 1810 by Louis-Gaspard d'Estournel.

The estate has changed hands several times throughout its history, beginning in 1852 when it was purchased by English banker Charles Cecil Martyns. In 1869 it was sold to the Spanish Errazu family, only to be sold again 20 years later, in 1889, to the Hostein family from Bordeaux. Through his marriage to Marie-Thérèse Hostein, Louis-Victor Charmolue, who also owned Château Montrose, acquired control of Cos d'Estournel in 1894. In 1917 it was sold to Fernand Ginestet. The chateau has remained in the Ginestet family ever since, becoming part of Domaines Prats in 1970, the combined property of the Ginestet and Prats families, and controlled by Bruno Prats.

In June 2008, it was announced that Michel Reybier, the current owner of Cos d'Estournel, has purchased Napa winery Chateau Montelena. However, in November 2008, this agreement was canceled, the termination of the transaction by Chateau Montelena allegedly due to the fact that Reybier Investments had "been unable to meet its obligations". From an estate of 100 hectares, the vineyard area extends over 70 hectares (170 acres), divided into 30 parcels, mainly composed of the grape varieties 60% Cabernet Sauvignon and 40% Merlot, with a small cultivation of Cabernet Franc and Petit verdot that seems participate too little in modern production. Annual production is typically 32,000 cases.