FRESNO (CBS/AP) – Four more California historic sites are joining the Cesar Chavez National Monument as places worthy of federal landmark protections.

Secretary of the Interior Ken Salazar announced on Friday that Drakes Bay Historic Archaeological District in Marin County, Knight’s Ferry Bridge in Stanislaus County, the U.S. Post Office and Courthouse in San Francisco and the U.S. Post Office and Courthouse in Los Angeles are considered important to the nation’s heritage.

The Drakes Bay site is where the English navigator is said to have first camped on American soil. The 379-foot Knights Ferry covered bridge is one of 100 of its type surviving. The San Francisco courthouse is an example of Beaux-Arts design, while the courthouse in Los Angeles was a scene of legal battles for Mexican-American civil rights.

KCBS’ Anna Duckworth Reports:

The National Historic Landmarks program qualifies sites for federal preservation advice.

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