While the gold rush of the nineteenth century in California was largely confined to the northern portion of the state, prospectors also fanned out to all regions of the state, seeking to strike it rich. In San Diego County, most of the mining exploration occurred in and around the town of Julian, but the largest and most productive mine was located a little bit further south, in what is now Cuyamaca Rancho State Park. In 1870, gold was discovered, and after a great deal of legal difficulties, the Stonewall Mine began operating. Over a fifty year period, the Stonewall Mine became the most productive and profitable mining operation in the county, producing over two million dollars of gold.