History of California's state highway system

The state highway system in the U.S. state of California dates back to 1896, when the state took over maintenance of the Lake Tahoe Wagon Road. Construction of a large connected system began in 1912, after the state's voters approved an $18 million bond issue for over 3000 miles (4900 km) of highways. The last large addition was made by the California State Assembly in 1959, after which only minor changes have been made.

The first state road was authorized on March 26, 1895, when a law created the post of "Lake Tahoe Wagon Road Commissioner" to maintain the Lake Tahoe Wagon Road (the 1852 Johnson's Cut-off of the California Trail), now US 50 from Smith Flat - 3 miles (5 km) east of Placerville - to the Nevada state line. The 58 mile (93 km) road had been operated as a toll road until 1886, when El Dorado County bought it; the county deeded the road to the state on February 28, 1896. Funding was only enough for minimal improvements, including a stone bridge over the South Fork American River in 1901.

Also in 1895, on March 27, the legislature created the three-person Bureau of Highways to coordinate efforts by the counties to build good roads. The bureau traveled to every county of the state in 1895 and 1896 and prepared a map of a recommended system of state roads, which they submitted to the governor on November 25, 1896. The legislature replaced the Bureau of Highways with the Department of Highways on April 1, 1897, three days after it passed a law creating a second state highway from Sacramento to Folsom - another part of what became US 50 - to be maintained by three "Folsom Highway Commissioners". This was the last highway maintained by a separate authority, as the next state road, the Mono Lake Basin State Road (now part of SR 120), was designated by the legislature in 1899 to be built and maintained by the Department of Highways.

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