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The Appellations Of California Wine - North Coast
The North Coast American Viticultural Area - Populated with the Most California Wineries
The North Coast American Viticultural Area (AVA) in California, covering more than three million acres, includes Napa, Sonoma, Mendocino and Lake counties, and portions of Marin and Solano counties. The area forms a slightly crooked rectangle, approximately 100 miles long and more than 50 miles wide. A winemaking mecca since the mid 19th century, today the area features about 800 wineries, nearly half of the total wineries in the state.
resource: Wine Institute