The highway system of
California is a network of roads owned and maintained by the state of California through the
California Department of Transportation (Caltrans). Most of these are numbered in a statewide system, and are known as State Route X (abbreviated SR X).
United States Numbered Highways are labeled US X, and
Interstate Highways are Interstate X, though Caltrans typically uses State Route X for all classes.
Interstate Highways and
U.S. Highways are assigned at the national level. Interstate Highways are numbered in a grid—even-numbered routes are east–west routes (with the lowest numbers along
Mexico and the
Gulf of Mexico), and odd-numbered routes are north–south routes (with the lowest numbers along the
Pacific Ocean). U.S. Highways are also numbered in a grid—even numbered for east–west routes (with the lowest numbers along
Canada) and odd numbered for north–south routes (with the lowest numbers along the
Atlantic Ocean). There are
21 Interstate Highways in California, ranging from
Interstate 5 to
Interstate 980. There are
seven current U.S. Highways including
U.S. Route 6 and
U.S. Route 395.
California State Routes are managed by Caltrans and designated by the
California State Legislature. The state route's signs are in the shape of a miner's
spade to honor the
California Gold Rush. Each
state highway in the U.S. state of California is assigned a Route (officially State Highway Route) number in the
Streets and Highways Code (Sections 300-635). Since July 1 of 1964, the majority of legislative route numbers, those defined in the Streets and Highways Code, match the sign route numbers. On the other hand, some short routes are instead signed as parts of other routes — for instance,
State Route 112 and
State Route 260 are signed as part of the longer
State Route 61, and
State Route 51 is part of
Interstate 80 Business.
California County Routes are marked with the usual
County route shield, and are assigned a letter for where they are located. For instance, county highways assigned "S" are located in
Southern California, ones assigned "J" are found in
Central California, and those assigned "A" are located in