Section 9.23 - Napa Valley(a)Name. The name of the viticultural area described in this section is "Napa Valley."(b)Approved maps. The maps showing the boundaries of the Napa Valley viticultural area are the:(1) "Mt. St. Helena" U.S.G.S. 7.5 minute quadrangle;(2) "Detert Reservoir" U.S.G.S. 7.5 minute quadrangle;(3) "St. Helena" U.S.G.S. 15 minute quadrangle;(4) "Jericho Valley" U.S.G.S. 7.5 minute quadrangle;(5) "Lake Berryessa" U.S.G.S. 15 minute quadrangle;(6) "Mt. Vaca" U.S.G.S. 15 minute quadrangle;(7) "Cordelia" U.S.G.S. 7.5 minute quadrangle;(8) "Cuttings Wharf" U.S.G.S. 7.5 minute quadrangle; and(9) Appropriate Napa County tax assessor's maps showing the Napa County-Sonoma County line.(c)Boundaries. The Napa Valley viticultural area is located within Napa County, California. From the beginning point at the conjuction of the Napa County-Sonoma County line and the Napa County-Lake County line, the boundary runs along- (1) The Napa County-Lake County line;(2) Putah Creek and the western and southern shores of Lake Berryessa;(3) The Napa County-Solano County line; and(4) The Napa County-Sonoma County line to the beginning point.T.D. ATF-79, 46 FR 9063, 1/28/1981, as amended by T.D. ATF-201, 50 FR 12533, 3/29/1985