27 CFR § 9.130 - San Ysidro District.
(a) Name. The name of the viticultural area described in this section is “San Ysidro District.”
(b) Approved maps. The appropriate maps for determining the boundaries of the San Ysidro District viticultural area are four U.S.G.S. Quadrangle (7.5 minute series) maps. They are titled:
(1) Gilroy, Calif., 1955 (photorevised 1981);
(2) Chittenden, Calif., 1955 (photorevised 1980);
(3) San Felipe, Calif., 1955 (photorevised 1971);
(4) Gilroy Hot Springs, Calif., 1955 (photorevised 1971, photoinspected 1978.)
(c) Boundary. The San Ysidro District viticultural area is located in Santa Clara County, California, within the Santa Clara Valley viticultural area. The boundary is as follows:
(1) The beginning point is the intersection of California State Highway 152 and Ferguson Road with an un-named wash, or intermittent stream, on the Gilroy, Calif., U.S.G.S. map;
(2) From the beginning point, the boundary follows the wash northeast as it runs co-incident with the old Grant boundary for approximately 3,800 feet;
(3) The boundary then follows the wash when it diverges from the old Grant boundary and continues approximately 2,300 feet in a northeasterly direction, crosses and recrosses Crews Road, then follows the wash southeast until the wash turns northeast in section 35, T.10S., R.4E., on the Gilroy Hot Springs, Calif., map;
(4) The boundary then diverges from the wash, continuing in a straight line in a southeasterly direction, across an unimproved road, until it intersects with the 600 foot contour line.
(5) The boundary then proceeds in a straight line at about the 600 foot elevation in a southeasterly direction until it meets the minor northerly drainage of the San Ysidro Creek;
(6) The boundary then follows the minor northerly drainage of San Ysidro Creek southeast for approximately 2,000 feet to the seasonal pond adjacent to Canada Road;
(7) From the seasonal pond, the boundary follows the southerly drainage of San Ysidro Creek for about 1,300 feet until it reaches the southwest corner of section 36, T.10S., R.4E.;
(8) The boundary then continues in a straight line in a southerly direction across Canada Road for approximately 900 feet until it intersects with the 600 foot contour line;
(9) The boundary follows the 600 foot contour line for approximately 6,000 feet in a generally southeasterly direction, diverges from the contour line and continues southeast another 1,200 feet until it meets an unimproved road near the north end of a seasonal pond on the San Felipe, Calif., U.S.G.S. map;
(10) The boundary follows the unimproved road to Bench Mark 160 at Highway 152.
(11) The boundary then follows Highway 152 in a northwesterly direction across the northeast corner of the Chittenden, Calif., U.S.G.S. map, and back to the beginning point at the junction of Ferguson Road and Highway 152.