27 CFR § 9.29 - Sonoma Valley.
(a) Name. The name of the viticultural area described in this section is “Sonoma Valley.”
(b) Approved maps. The maps showing the boundaries of the Sonoma valley viticultural area are entitled:
(1) “Cuttings Wharf, Calif.”, 1949 (photorevised 1968 and photoinspected 1973), 7.5 minute quadrangle;
(2) “Petaluma Point, Calif.”, 1959 (photorevised 1968 and photoinspected 1973), 7.5 minute quadrangle;
(3) “Sears Point, Calif.”, 1951 (photorevised 1968), 7.5 minute quadrangle;
(4) “Petaluma River, Calif.”, 1954 (photorevised 1968 and 1973), 7.5 minute quadrangle;
(5) “Glen Ellen, Calif.”, 1954 (photorevised 1968 and photoinspected 1973), 7.5 minute quadrangle;
(6) “Cotati, Calif.”, 1954 (photorevised 1968 and 1973), 7.5 minute quadrangle;
(7) “Santa Rosa, Calif.”, 1954 (photorevised 1968 and 1973), 7.5 minute quadrangle;
(8) “Kenwood, Calif.”, 1954 (photorevised 1968 and photoinspected 1973), 7.5 minute quadrangle; and
(9) Appropriate Sonoma County tax assessor's maps showing the Sonoma County-Napa County line.
(c) Boundaries. The Sonoma Valley viticultural area is located within Sonoma County, California. From the beginning point at the junction of Tolay Creek and San Pablo Bay, the boundary runs:
(1) Northerly along Tolay Creek to Highway 37;
(2) Westerly along Highway 37 to its junction with Highway 121;
(3) Northwesterly in a straight line to the peak of Wildcat Mountain;
(4) Northwesterly in a straight line to Sonoma Mountain to the horizontal control station at elevation 2,271 feet;
(5) Northwesterly in a straight line to the peak of Taylor Mountain;
(6) Northeasterly in a straight line to the point at which Los Alamos Road joins Highway 12;
(7) Easterly in a straight line to the peak of Buzzard Peak;
(8) Easterly in a straight line to the peak of Mount Hood;
(9) Easterly in a straight line to an unnamed peak located on the Sonoma County-Napa County line and identified as having an elevation of 2,530 feet (This unnamed peak is located in the northeast quarter of Section 9, Township 7 North, Range 6 West, Mt. Diablo Base and Meridian);
(10) Southerly along the Sonoma County-Napa County line to the point at which Sonoma Creek enters San Pablo Bay; and
(11) Southwesterly along the shore of San Pablo Bay to the beginning point.