Sonoma Valley received its designation as an AVA in 1987. Situated across 60,065 acres, Sonoma Valley includes sub-appellations Bennett Valley, Los Carneros, Sonoma Mountain, and Moon Mountain District Sonoma County. The Sonoma Mountain protects Sonoma Valley from the wet and cool influence of the nearby Pacific Ocean. The Sonoma Mountains to the west help protect the valley from excessive rainfall. The cool air that does affect the region flows northward up from San Pablo Bay through the Los Carneros region.