San Ysidro Mountain

** Use at Your Own Risk **

See the Retired Peak Guides in the Archives for Microsoft Word and other versions of this peak guide.

31I

San Diego County, about 9 miles west of Borrego Springs, 137 miles from Los Angeles

Take I-15 south to Temecula.
Take the second off-ramp for SR 79, signed "79 South / Indio". Turn left (east) on SR 79 for 37 miles to the town of Warner Springs.
Continue south of Warner Springs on SR 79 for 3.5 miles to a junction with S2 coming in from the left. Turn left onto S2.
Drive southeast 4.7 miles to S22. Turn left.
Drive east on S22 for 6.6 miles to the Anza-Borrego State Park Boundary, which is signed at the top of a rise in the road. Park on the road shoulder just past the rise at the end of the fence on the left side of the road.

From the parking area (4200'), head north up the ridge, parallel to the fence but eventually veering northeast, following openings through cholla and scrub brush.
Within a mile of the highway, the fence takes about a 1/4 mile jog to the east. When you meet this east-west fence portion, turn east around the fence corner, ending up about 1/4 mile south of a prominent formation known as Chimney Rock. Head north past this rock and the next bump on their east sides.
Then go north up a ridge and over bump 5326', which has a register on top ("White Benchmark").
Continue north from White BM through moderate to heavy brush along the east side of the Thimble.
Upon meeting a major gully about 0.2 mile to the northeast of the Thimble, turn west and ascend the gully to the saddle at its head.
From the saddle, go north up brushy slopes to the summit.

San Ysidro Peak lies within the Anza-Borrego State Park, but no fee is required when parking along the shoulder of paved road S22.

Please report any corrections or changes to the Mountain Records Chair.