Forty different nationalities were represented among the miners of Campo Seco during the early years, making it perhaps the most cosmopolitan of all the mining camps in the Gold Country. The area was first prospected by Mexican miners in 1849, and by the following year quite a camp had grown up around them. It was due to the severe scarcity of water that the place got its name, Campo Seco, meaning "dry camp" in Spanish.
The camp is located on Oregon Gulch, which was named for a group of prospectors from Oregon who worked the area during 1849. By 1854, the town had three hotels, two churches, several saloons, a brewery, livery stable, smithy, restaurant, post office, stores, and many homes and orchards. Most of the buildings were of wood and up to this time the camp had not suffered a serious fire. The fire of 1854 nearly wiped out the entire town. As the placers were still producing—a ninety-three ounce nugget was found that year—and several hard rock mines were in operation, the town was rebuilt. Most of the stone structures remaining today date from after this fire.
In 1856, the Mokelumne Water Company provided the camp with water. Unfortunately, the placers were pretty much exhausted by then and the quartz veins were also playing out. People began to move away and it seemed as if the town would follow the path of so many of its contemporaries.
Copper. In 1859, two men discovered it. Located between the town and the Mokelumne River were extensive copper lodes which, unlike the mines at Copperopolis, also produced gold. Mr. J.K. Harmon acquired the mine, built a smelter, and operated it very successfully for many years, the gold contributing to help pay expenses for the mine. Harmon consolidated several mines in the 1890s and operated as the Penn Chemical Company, which is credited with producing sixty-two thousand ounces of gold, nearly eighty million pounds of copper, twelve million pounds of zinc, six hundred thousand pounds of lead, and two million ounces of silver.
Campo Seco is located four miles north of Valley Springs via Campo Seco Road. Valley Springs is located eight miles from San Andreas via Hwy 12.
A row of Stone Ruins is the first thing you’ll notice upon entering Campo Seco. Perhaps four or five stores once occupied these remains during the Gold Rush and beyond, most likely general stores, saloons, or maybe an express office as the Adams Express Company operated here for a time. The workmanship that went into these buildings is still evident, especially around the doors and windows, where extra care was used in placing the quarried blocks and carefully selected stones. Shaded by a number of trees growing both in and around the roofless walls, these ruins provide an intriguing place to wander about.
A Stone Monument is located near the row of ruins. It gives a brief outline of Campo Seco history and tells of the mysterious cork oak tree.
The Chinese Store Ruins are the last substantial remains of what was once a large Chinese section of town. The buildings were constructed of stone and a small amount of lumber, with mud, clay, and moss used for chinking the holes. The walls were eighteen inches thick and were fitted with the familiar iron doors and shutters of the era. The two buildings reportedly belonged to men of different tongs, and although located right next door to each other, miners who dealt with one would not trade with the other.
Several other Stone Ruins and Foundations lay scattered about the area, the origins of which have long since been lost. Another structure of interest is the small wooden building with the ominous "Toxic Pits" sign attached. I'd advise staying away from that one.