Cuyamaca is a region of eastern San Diego County. It lies east of the Capitan Grande Indian Reservation in the western Laguna Mountains, north of Descanso and south of Julian. Named for the 1845 Rancho Cuyamaca Mexican land grant, the region is now dominated by the 26,000-acre (110 km2) Cuyamaca Rancho State Park. Within the park is the prominent Cuyamaca Peak, the second-highest mountain in San Diego County at 6,512 feet (1,984.9 m).

Cuyamaca Rancho State Park is a state park in inland San Diego County, Southern California, United States, located 40 miles (64 km) east of the metropolitan area of San Diego. The park is situated near the southernmost reaches of the vast Cleveland National Forest, as well as the Cuyamaca and Laguna Mountains of the Peninsular Ranges. The park's 26,000 acres (11,000 ha) of land features pine, fir, and oak forests, interspersed with meadows, creeks and streams that exist due to the relatively high elevation of the area when compared to its surroundings. The park includes the 6,512-foot (1,985 m) Cuyamaca Peak, the second-highest point in San Diego County.