The Santa Cruz Mountains AVA is an American Viticultural Area centered on the Santa Cruz Mountains. It includes three counties in California:  Santa Clara, Santa Cruz and San Mateo. Recognized as an AVA in 1981, the Santa Cruz Mountains Appellation was among the first to be defined by its mountain topography. Based on elevation, it largely follows the fog line along the coast, extending down to in the east (San Francisco Bay side) and in the west (Monterey Bay side), and encompasses the highest ridgetops at 3000+ elevation.