SR 1 is part of the California Freeway and Expressway System, and through the Los Angeles metro area, Monterey, Santa Cruz, San Francisco metro area, and Leggett is part of the National Highway System,</ref> a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. SR 1 is eligible to be included in the State Scenic Highway System; however, only a few stretches between Los Angeles and San Francisco have officially been designated as a scenic highway, meaning that there are substantial sections of highway passing through a "memorable landscape" with no "visual intrusions", where the potential designation has gained popular favor with the community. The Big Sur section from San Luis Obispo to Carmel is an official National Scenic Byway.