The Santa Clara Valley AVA is an American Viticultural Area located in Santa Clara County, California. The area served an important role in the early history of California wine and was home to the pioneer winemakers Paul Masson and Charles Lefranc. The AVA boundary was defined in 1989. It includes the historic winegrowing areas of Santa Clara County which were not already part of the Santa Cruz Mountains AVA as well as the area near Mission San José in Alameda County and a small part of San Benito County.