Around 1850, miners created these piles of boulders as they searched for placer gold in the sands beneath them. They used both windlass and water-powered derricks to lift and stack the rocks, with water power developed through wing dams and water wheels in the Klamath River. Belts and pulleys converted that power to a gear box, where an operator controlled the boom to raise and move the boulders. After the large rocks were removed, the gravel and sand were placed in a sluice box, washed, and the gold extracted. Nuggets weighing up to 16 ounces were found in the Klamath River.