Highway Map of the State of California

Mid-1920s road map of California published by the state’s Automobile Association.

Organized as an offshoot of The Automobile Club of California in 1907, the California State Automobile Association (CSAA) is one of the oldest and largest affiliates of the American Automobile Association. As part of its services to the public, the CSAA began erecting road signs and publishing maps in 1909. This example dates to sometime shortly after 1925, at which point the CSAA moved into its new headquarters at 150 Van Ness Avenue in San Francisco. It remained there until moving locations in 2007, and the building was razed in 2013.

The color lithograph image uses lines of varying colors and thickness to identify four different classifications of roads across the state – Main Roads, Roads of Second Importance, Roads of Third Importance, and All Other Roads. Railroads, rivers and streams, and county boundaries are also depicted according to the legend in the lower right. A dense assortment of toponyms are clustered throughout the Central Valley, reflecting its early development in comparison to today’s popular spots in Southern California and the Bay Area.

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