In 1834, Mariano G. Vallejo's brother-in-law, John B. R. Cooper, constructed California's first known power-operated commercial sawmill. In addition to sawing redwood lumber, the mill and surrounding settlement served as a barrier to Russian encroachment from the west. Located 1/3 mile east on Mark West Creek, the water-powered mill was destroyed by flood in the winter of 1840-41.

California Registered Historical Landmark No. 835

Plaque placed by the State Department of Parks and Recreation in cooperation with the California Division of Forestry and the Forest Products Indistries of California.
January 31, 1970