Château Roûmieu-Lacoste traces its origins to 1890, when the Lacoste family purchased a small estate in Barsac. The property took its current name when Georges Dubourdieu married Marguerite Lacoste, and today is run by the fifth generation of the Dubourdieu family. The estate's vineyards sit on the Haut-Barsac plateau in clay-limestone and silt soils over a fractured rock subsoil, with vines averaging 45 years of age. The wine is 100% Sémillon, hand-harvested in successive passes through the vineyard, and aged 18 months in barrel. The estate holds HEV Level 3 certification (High Environmental Value).