Custom House Constructed in 1827 by the Mexican government to collect custom duties from foreign shipping, a principle revenue source when Monterey was the capital of Alta California, Mexico's northernmost province. Thomas O. Larkin, US consul to Alta California, contracted with the Mexican government in 1841 to rebuild and enlarge the Custom House. Commodore John Drake Sloat raised the American flag over this building on July 7, 1846 to signal the passing of California from Mexican to American rule. Restored through the efforts of the Native Sons of the Golden West with the assistance of the people of California. State Registered Historical Landmark No. 1 Registered June 1, 1932 National Historic Landmark designated 1960 Plaque placed by the Native Sons of the Golden West, the California State Parks Foundation, and California State Parks Rededicated 2014, the 150th anniversary of California State Parks