Malakoff Diggins State Historic Park is a state park unit preserving the largest hydraulic mining site in California, United States. The mine pit and several Gold Rush-era buildings were listed on the National Register of Historic Places as the Malakoff Diggins-North Bloomfield Historic District. The \"canyon\" is 7,000 feet long, as much as 3,000 feet wide, and nearly 600 feet deep in places. Visitors can see huge cliffs carved by mighty streams of water, results of the mining technique of washing away entire mountains of gravel to wash out the gold. The park is a 26-mile drive north-east of Nevada City, California, in the Gold Rush country. The 3,143-acre park was established in 1965.
