California's luscious Napa Valley is probably the second most celebrated wine-growing region in the world, after France's Bordeaux, and is the second biggest tourist draw to the state of California bringing in nearly five million tourists annually. Almost as famous is Sonoma Valley. Where the Valleys rule supreme, however, is the art of modern winemaking. Here the practice of cold and maloactic fermentation, and the use of heaters and wind machines to combat frost are commonplace. Some of the more popular grape varieties coming out of the over 300 wineries in this region include Cabernet Sauvignon, Chardonnay, Pinot Noir and Merlot. Vineyards range from tiny to immense, and touring Napa and Sonoma Valleys offers a range of experiences from riding up a mountain in a gondola and learning about the process of winemaking on a vineyard tour to eating in a quaint restaurant and aintique shopping in one of the small towns in the area.