There are a number of highways that criss-cross this huge state park and require no fee to travel.
California Route 78 runs east to west through the middle of the park while County Routes
S1, S2, S3 and S22 links the various sections of the park.
Southern Emigrant Trail Self-Guided Auto Tour
Much of Highway S2 parallels the old trail known at times as the Sonora, Colorado River, and the Southern Emigrant trails, which was the route into California for a number of travelers in the 18th and 19th centuries.
A part of this old trail was used by the Spanish, and from 1826 it was an element of the Mexican mail route. Kit Carson was familiar with it, and part of it served as the route for General Stephen W. Kearny and the Army of the West at the time of the Mexican War.
In 1857 a portion served as the route of the San Antonio and San Diego mail line, better known as the "Jackass Mail" (they left it to travel through Oriflamme Canyon to San Diego). After improving the trail, the Butterfield Overland Mail stages followed it through Vallecito from 1858 - 1861 (Highway 79 follows the stage route from S2.).
The Gila / Southern Emigrant Trail was briefly the most popular southern route taken to California by emigrants and the '49ers on their way to the Gold Rush. It was a route hard on man and beast, and by the Civil War other routes had become more popular, and it had largely fallen into disuse.
Erosion Road Self-Guided Auto Tour
One-way, 18-mile (1 hour) drive east from the Visitor Center along County Road S-22 (Borrego-Salton Sea Way). Erosion Road tour is an introduction to the geology of the Anza-Borrego Desert. It includes stops at the Coyote and Santa Rosa Mountains, Font's Point, Clark Dry Lake, Font's Point Wash and an overlook of the Borrego Badlands and Salton Sea. It demonstrates the constant conflict of geologic forces at work here -- faulting and erosion -- to form mountains, canyons, alluvial fans, playas, bajadas etc.. The geology of Anza-Borrego also highlights the effects of the San Jacinto Fault, the most active branch of the famous San Andreas Fault. A brochure with map is available from park offices. It describes each of the 10 stops, identified by the mileage the marker which precedes it, plus the fractional mileage off-road from that marker.
