The Santa Ynez Valley AVA is an American Viticultural Area located in Santa Barbara County, California. It is part of the larger Central Coast AVA, and contains the greatest concentration of wineries in Santa Barbara County. The valley is formed by the Purisima Hills and San Rafael Mountains to the north and the Santa Ynez Mountains to the south. Chardonnay is the most planted grape varietal in the cooler, western portion of the valley, and Rhône varietals are more successful in the east.