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This Art Deco courthouse replaced the earlier Greek Revival courthouse demolished in 1940, but it too has now been succeeded by a newer 1960s era building next door. Today this building houses the San Luis Obispo County Department of Planning and Building.


  • SLO City - Resource 125

The historical markers, located just to the right of the Osos Street entrance, note that the architects were A.R. Walker and P.A. Eisen, the construction superintendent was Charles D. Eggleston, and the county supervisors in 1940 were Claude Arnold, Henry Twisselman, Alfred Ferrini, John Norton, and A.A. Erhart.

The San Luis Obispo Court system today consists of a cluster of adjacent buildings including: Criminal Court at 1050 Monterey Street, next door to this building, and the Civil Court behind that building at 1035 Palm Street.

Before statehood in 1850, California had no defined system of local government. During the Spanish period, there were North and South provinces for Alta California. In the Mexican period, there were five vaguely defined prefectures centered on San Diego, Los Angeles, Santa Barbara, Monterey and San Francisco. None of these entities had any powers of self rule; they were merely geographic subdivisions of the central government.

In 1850, the new Legislature created 27 counties. These were self-governing entities in the American tradition, with an elected board of supervisors and various officers, such as sheriff, treasurer, auditor, clerk and district attorney.

In California, counties have two sets of responsibilities: (1) administration of State laws, and (2) purely local governance. In the first group are such functions as criminal justice, public health, social services, and elections. Local functions include road maintenance, land use planning, parks, libraries, and commercial regulation. Most school districts are organized inside County boundaries.

Almost from the beginning of Statehood, the Legislature created new counties and adjusted boundaries of existing ones. Some counties were created in law, but never actually organized, and one was abolished. Today there are fifty-eight counties, including the unique city-county of San Francisco, and San Bernardino, the world’s largest county.

San Luis Obispo was one of the original twenty-seven counties and today retains its boundaries largely intact. With 3,304 square miles of land area, the County is the 17th in size and ranks 23rd in population, with over 269,000 residents.


Historical Marker Database for the Site of First County Court House https://www.hmdb.org/marker.asp?marker=16560