Anza-Borrego Desert State Park is a state protected land located in Southern California primarily within eastern San Diego County, with portions within Imperial and Riverside counties. At 600,000 acres (2,400 km²) and one fifth of San Diego County within its borders, Anza-Borrego Desert is the largest state park in California and the second largest within the continental United States after Adirondack Park in New York. The park is two-hours away from the cities of San Diego, Riverside and Palm Springs. The park is named after Spanish explorer Juan Bautista de Anza and the Spanish word borrego, for bighorn sheep.

Vista of the desert

Panoramic image looking west from Font's Point.

Bighorn Sheep at Palm Canyon.

The park includes 500 miles (804 km) of dirt roads, 12 wilderness areas and 110 miles (180 km) of hiking trails provide visitors with an opportunity to experience the Colorado Desert. Listening devices for the hearing impaired are available in the visitor center. Anza-Borrego Desert State Park is one of 55 California State Parks with wi-fi access in one or more areas. Footage shot at this park was used in the 2005 feature film Serenity.

Many visitors approach from the east via California Highways S22, S2, or 78. Visitors from San Diego via Highways 79 and 78 have the added pleasure of driving through the mountainous Cuyamaca Rancho State Park—quite a different experience from Anza-Borrego. The highways from the east climb to 2,400 feet (731 m) or so and then descend about 2,000 feet (609 m) to the valley. Where the highway breaks out of the high-country vegetation, it reveals the great bowl of the Anza-Borrego desert. The valley spreads below, and there are mountains all around. The highest are to the north—the Santa Rosa Mountains. The highest mountains are wilderness, with no paved roads in or through. They have the only all-year-flowing watercourse in the park.