County routes in California

County Routes in California
Example of a California county route shield.
System information
Notes:	All classes of state-numbered highways are generally state-maintained.
Highway names
Interstates:	Interstate X (I-X) or Route X
US Highways:	U.S. Route X (US X) or Route X
State:	State Route X (SR X) or Route X
System links
County routes in California

County routes in the U.S. state of California are controlled and maintained by the respective counties in which they are located. However, they are generally patrolled by the state's California Highway Patrol.

County routes are typically designated with a letter (A, B, D, E, G, J, N, R, or S, depending on the region of the state, with several counties split between two region prefixes) followed by a number (example: G2). Therefore, the county routes are sorted alphabetically, from the northernmost region of California to the southernmost region. Routes with letters (A, B, D) are in the region of Northern California, letters (E, G, J) are in Central California, and (N, R, S) are in Southern California. Routes in Lake and San Bernardino Counties are designated by numbers only.

These routes are all part of the California Route Marker Program, which was established in 1958. This program was incorporated into the National Uniform County Route Marker Program created by the National Association of Counties in 1967. Not all counties choose to use the same marker; some have different systems of numbering their county routes.

The county routes are alphabetically sorted by the prefix letter in its shield, followed by the corresponding number.