Empire Mine

Empire Mine State Historic Park in Grass Valley preserves the surface buildings of one of the richest gold mines in the world. Mining began after George D. Roberts found a gold-bearing ledge on the hillside in 1850. The mine passed through several owners, and William B. Bourn took over management in 1867. It later merged with the neighboring Pennsylvania and North Star groups. When it closed in 1956, it was the oldest quartz mine in continuous operation in the United States, with an estimated $120 million in gold recovered. Surviving structures include the 1896 Bourn mansion, built of rough granite and brick, the mine office and refinery, and the circa 1905 clubhouse. San Francisco architect Willis Polk designed the mansion, office and clubhouse. Quarry stone from the mine was used in the walls. The mansion sits among tall pines, behind ornate brick and rock walls, and shows its age through weathered mortar and broken leaded windows.