This mortise-and-tenon Greek Revival courthouse, erected in 1854, is California's oldest court of law and has served continuously as the seat of county government since 1854. During the 19th Century, landmark mining cases setting legal precedent were tried here, and much United States mining law is based on decisions emanating from this historic courthouse.

California Registered Historical Landmark No. 670

Plaque placed by the State Department of Parks and Recreation in cooperation with the Mariposa County Bicentennial, July 3, 1976.