Napa Valley is a viticultural area located in Napa County, California, United States. Napa Valley is considered one of the premier wine regions in the world, with records of commercial wine production in the region dating back to the nineteenth century, but premium wine production only began in the 1960s.

Napa Valley has a generous climate that provides vintage-to-vintage consistency and exceptional quality that few other winegrowing regions can boast. Napa Valley has a remarkable diversity of microclimates, weather and geography, as well as some of the most diverse soils found on earth. As a result, an number of premium grape varietals thrive. John Patchett established the Napa Valley's first commercial vineyard back in 1858. Viticulture in Napa suffered several setbacks in the late 19th and 20th centuries, including phylloxera, Prohibition and the Great Depression. In 1976, the region received a boost from the Paris Wine Tasting of 1976, which featured a Napa Valley Chardonnay and Cabernet Sauvignon besting several famous French labels in a blind tasting - cementing the region's reputation as a producer of world class wines.

Napa Valley features more than 450 wineries - though just 48km long and a few km's wide, the valley is flanked by the Mayacamas Mountain Range on the western and northern sides the Vaca Mountains on the eastern side. The soil in the southern end of the valley consists mainly of sediments deposited by advances and retreats of San Pablo Bay while the soil at the northern end contains a large volume of volcanic lava and ash.

Among the internationally acclaimed wines produced in this small region are Cabernet Sauvignon, Merlot, Pinot Noir, Chardonnay, Sauvignon Blanc, Zinfandel and Cabernet Franc, to name a few. In spite of its international reputation, Napa Valley is one of the smallest winegrowing regions in the world. The region's established viticultural practices result in low yields of high-quality grapes, from which skilled winemakers craft Napa Valley's renowned wines.