Known throughout the wine world as the "king of red wines," Cabernet Sauvignon is the most popular and widespread red grape varietal in the world. For centuries it's been the main grape planted in the Bordeaux region of France (and, therefore, the main component of Bordeaux wines). It has since spread to most every winegrowing region in the world, including Spain, Chile, Australia, South Africa, and California. In fact, California has practically founded its premium wine-making reputation on this small, tough-skinned grape. Why is Cabernet Sauvignon so popular? Because it's traveled the world and retained its individual character; it's adaptable to a variety of climates and soils; it's very resistant to disease and frost; and it's legendary for its aging ability (if you're going to age a wine, this is the one to age). Because Cabernet Sauvignon has a high skin-to-juice ratio, thick skins, and small berry size, it's also high in tannins. It's almost always blended with "softer" wines such as Merlot and Cabernet Franc (or, if you're making an Italian Supertuscan, with Sangiovese) to assuage its inherent bitterness. The result is a medium- to full-bodied wine with a firm structure and mouth-drying finish. Because Cabernet Sauvignon is a complex grape that is almost always aged in oak, it exhibits numerous aromas ranging from chocolate and black cherry to cassis, green bell pepper, mint, asparagus, cedar, eucalyptus, coffee, tobacco, and tar. It's best matched with red meats such as lamb and beef, as well as strong cheeses. Cabernet Sauvignon is one of the four red wines (the others are Merlot, Syrah, and Pinot Noir) that make up the nine classic varietals (there are five white classic varietals: Chardonnay, Chenin Blanc, Riesling, Sauvignon Blanc, and Sémillon.)