The Donald and Sylvia McLaughlin Natural Reserve is a 7,050-acre protected area in Northern California’s Blue Ridge Berryessa region, spanning Napa and Lake counties on the former McLaughlin Mine site. Established in January 1993 through an agreement between Homestake Mining Company and the University of California, it became a research and teaching facility within the university’s Natural Reserve System while remaining on company-owned land. The reserve protects interior chaparral and woodlands, supports scientific study through the Ray Krauss Field Station and later greenhouse funding, and preserves a landscape shaped by both mining history and reclamation, including remnants of Knoxville, an 1880s mining settlement.