The Oak Knoll District of Napa Valley received its designation as an AVA in 2004 and is a sub-appellation of the Napa Valley AVA. Located on 8,300 acres at the most southern end of Napa Valley, its proximity to San Pablo Bay and low elevation results in a climate that is moderate and cool. The soils of the region are an alluvial mix of sand and clay and drain very well. The colder climate gives this region an extended growing season that allow the grapes to develop a balanced acidity. Given the moderate climate and relatively consistent elevation, Oak Knoll has more vines planted to it than any other region in Napa Valley. A wide variety of wine grapes do well in this climate; however, the most common are Merlot, Chardonnay and Cabernet Sauvignon.