The historic Capitol was designed by architects M. F. Butler and Ruben Clark. Its style is an adaptation of Roman Corinthian architecture. Work began in 1860 and by late 1869 the Capitol was partly occupied. In 1874, construction ended at a cost of $2.45 million. The west wing which once housed all branches of government is now a legislative facility. Its design and construction are tributes to California's pioneer architects, craftsmen, and builders.

Citation from California Office of Historic Preservation