This redwood structure was completed in 1868 by William Chapman Ralston, San Francisco financier. Incorporating Count Cipriani's earlier villa, this enlarged mansion with its mirrored ballroom became the symbol of the extravagance of California's Silver Age. It anticipated features later incorporated into Ralston's Palace Hotel in San Francisco.

California Registered Historical Landmark No. 856
Plaque placed by the California Department of Parks and Recreation in cooperation with the California Historical Society.
November 5, 1972