Undoubtedly the most important viticultural region of the country of Argentina is Cuyo, the arid and red-soiled area within central-west Argentina which produces over eighty percent of the nation's wine each year. Cuyo represents the finest aspects of Argentinian wine making, with wineries in the region celebrating their traditions which stretch back to the sacramental wines first introduced to the country by Spanish settlers hundreds of years ago. As with much of Argentina, Cuyo is most famous for the production of Malbec wines, with Malbec grapes thriving prodigiously in the hot climate of the region, reaching full ripeness in ways they rarely could in their native France, and producing wines of exceptional flavor and quality. The Desaguadero River is the key water source in this otherwise dry and dusty region, and successful irrigation projects have helped bring water to even the driest vineyards within Cuyo. The purple Malbec variety grapes which now grow all over the Old and New Worlds had their origins in France, where they are one of the few grape varieties allowed to be used in the highly esteemed blended wines of Bordeaux. However, it is perhaps the New World Malbec wines which have attracted the most attention in recent years, as they thrive in hot southern climates in ways they cannot in their native country, where the damp conditions leave them highly vulnerable to rot. Malbec grapes are renowned for their high tannin content, resulting in full-bodied red wines packed with ripe, plummy flavors and held in their characteristically dark, garnet colored liquid. In many countries, Malbec is still used primarily as a varietal for blending, as it adds a great level of richness and density to other, lighter and thinner varietals. However, single variety Malbec wines have been greatly on the rise in recent years, with some fantastic results and big, juicy flavors marking them out as a great wine for matching with a wide range of foods.