Rancho Cucamonga is a city located just south of the foothills of the San Gabriel Mountains and Angeles National Forest in San Bernardino County, California, United States. About 37 mi (60 km) east of Downtown Los Angeles, Rancho Cucamonga is the 28th most populous city in California. The city's seal, which centers on a cluster of grapes, alludes to the city's agricultural history including wine-making. The city's proximity to major transportation hubs, airports, and highways has attracted the business of several large corporations, including Coca-Cola, Frito-Lay, Big Lots, Mercury Insurance Group, Southern California Edison, and Amphastar Pharmaceuticals.

The San Gabriel Mountains comprise a mountain range located in northern Los Angeles County and western San Bernardino County, California, United States. The mountain range is part of the Transverse Ranges and lies between the Los Angeles Basin and the Mojave Desert, with Interstate 5 to the west and Interstate 15 to the east. The range lies in, and is surrounded by, the Angeles and San Bernardino National Forests, with the San Andreas Fault as its northern border.