Lake County's century-old classic courthouse, designed by A.P. Pettit in 1871, served as the seat of county government from 1871 until 1968 when it was replaced by the new courthouse. Among the court's landmark cases were the White Cap Murders, a notorious episode in vigilantism held here in 1890, and several water right cases which set precedent still in effect.

California Registered Historical Landmark No. 897

Plaque placed by the State Department of Parks and Recreation in cooperation with the Lake County Bicentennial Committee and the Old Courthouse Committee, January 29, 1978.