A typical postmile marker on State Route 1 in Monterey County

California uses a postmile system on all of its state highways, including U.S. Routes and Interstate Highways. State Route 1, often called Highway 1, is a State highway that runs along much of the Pacific coast of the U Monterey County is a county located on the Pacific coast of the U State highway, state road or state route can refer to one of three related concepts two of them related to a State government in a country that is divided The system of United States Numbered Highways (often called U The Dwight D Eisenhower National System of Interstate and Defense Highways, commonly called the Interstate Highway System (or simply the Interstate System) The postmile markers indicate the distance a route travels through individual counties, as opposed to mile markers that indicate the distance traveled through a state.

Format

A postmile marker is a metal paddle placed along the state highway. Each marker is stenciled with the route, county, and postmile at that location. ^[1]

California is the only state in the United States that does not use mile markers on its highways. According to the Manual on Uniform Traffic Control Devices, they, however, encouraged the use of mileposts like all the other states and stated that:

Current formats

Bridge

One of the common formats for postmiles are located on a freeway on bridges over cross streets. According to Caltrans, it displays the name of the bridge, the county and route number, and the postmile. ^[2] The postmile is often painted onto the piers and/or abutments of bridges and overpasses.

Postmile markers

These are the white markers placed at one-mile (1. 6 km) intervals, with additional markers placed at significant features along the highway such as bridges and overpasses, junctions, or culverts. The markers are roughly the same size as a standard milepost used elsewhere, but they are white with black text.

Callbox

Postmiles are also shown on callboxes. A call box or callbox is a (usually metal box containing a special-purpose direct line telephone or other Telecommunications device, which A blue placard is mounted on each of the state's callboxes, the top of which shows what county one would be in, and on the bottom, it shows the 2-letter county abbreviation, along with the route number and the location's postmile (in tenths of miles). ^[2]

County prefixes

Alphabetic prefixes on postmile markers and bridges differ from callbox prefixes because the callbox system is maintained by each county, while Caltrans maintains postmile markers and bridge signs. The California Department of Transportation ( Caltrans) is a Government department in the U ^[3] The following table lists postmile and callbox prefixes by county.

Postmile SC 12. 6 labeled on a callbox for I-280 in Santa Clara County

Official postmile definitions

Listed in miles, postmile values usually increase from south to north or west to east depending upon the general direction the route follows within the state. Interstate 280 (I-280 is a 57 mile (92 km long interstate Freeway in the San Francisco Bay Area metropolitan area of Northern California Santa Clara County is a County located in the San Francisco Bay Area of the U Alameda County is a county in the US state of California. It occupies most of the East Bay region of the San Francisco Bay Area. Orange County is a county in Southern California, United States. Alpine County is the smallest county, by population in the US Placer County (from Spanish: placer - "pleasure" is a county located in the Sierra Nevada of the U Amador County is a county located in the Sierra Nevada of the U Plumas County is a county located in the Sierra Nevada of the U Butte County is a County located in the Central Valley of the U Riverside County is a County located in the southeastern part of the U Calaveras County is a County located in the Gold Country of the U Sacramento County is a county in the US state of California. The County seat is the city of Sacramento, the State capital Colusa County is a County located in the Central Valley of the U San Benito County is a county located in the Coast Range Mountains of the U Contra Costa County ( Spanish for "opposite coast" is a suburban county in the San Francisco Bay Area of the U San Bernardino County is a county in the US state of California. Del Norte County sits in the far northwest corner of the US state of California, located on the Pacific coast south of Oregon. San Diego County is a County located on the Pacific Ocean in the far southwest of the U El Dorado County is a County located in the Gold Country of the U The City and County of San Francisco is the fourth most populous city Fresno County is a County located in the Central Valley of the U San Joaquin County is a county located in Central Valley of the U Glenn County is a county located in the Central Valley, in the northern part of the U San Luis Obispo County is a county located along the Pacific Ocean in the Central Coast of the U Humboldt County is located on the far North Coast of California. San Mateo County ( "san muh-TAY-o") ( Spanish for: St Imperial County is a County located in the Imperial Valley, in the far southeast of the U Santa Barbara County is a County located on the Pacific coast of the southern portion of the U Inyo County is located in east-central California in the southwestern United States, on the east side of the Sierra Nevada Mountains and south of Yosemite Santa Clara County is a County located in the San Francisco Bay Area of the U Kern County is a County located in the southern Central Valley of the U Santa Cruz County is a county located on the Pacific coast of the U Kings County is a County located in the Central Valley of the U Shasta County is a county located in the northern portion of the U Lake County is a County located in the north central portion of the U Sierra County is a county located in the Sierra Nevada of the U Lassen County is a county located in the northeastern portion of the U Siskiyou County is a County located in the far northernmost part of the U Los Angeles County is a county in California and is by far the most populous county in the United States. Solano County is a County located in Bay-Delta region of the U Madera County is a County of the US state of California, located in the Central Valley and the Sierra Nevada north of Sonoma County, located on the northern coast of California, is one of the northernmost counties of the nine county Greater San Francisco Bay Area, U March 11, 1889 | Stanislaus County is a County located in the Central Valley of the state of California, between Stockton and Fresno. Mariposa County is a County in the US state of California, located in the western foothills of the Sierra Nevada mountains Sutter County is a county located along the Sacramento River in the Central Valley of the U Mendocino County is a County located on the north coast of the U Tehama County (pronounced teh-HAY-muh is a county located in the northern part of the U Merced County (pronounced "Mer-SED" is a County located in the Central Valley of the U Trinity County is a large rugged and mountainous heavily forested county located in the northwestern portion of the U Modoc County is a county located in the far northeast corner of the U Tulare County is a county located in the Central Valley of the U Mono County is a County located in the east central portion of the U Tuolumne County (tuːˈɒləmi "To All o' Me" with a silent N is a county located in the Sierra Nevada of the U Monterey County is a county located on the Pacific coast of the U Ventura County is a county in the southern part of the US state of California ( Southern California) Napa County is a County located north of the San Francisco Bay Area in the U Yolo County is located in the northern part of the US state of California, bordered by the counties of Sacramento, Solano, Nevada County is a county located in the Sierra Nevada of the U Yuba County is located in the US state of California 's Central Valley, north of Sacramento, along the Feather River. The postmile values increase from the beginning of a route within a county to the next county line. The postmile values start over again at each county line.

Enforcement officers, maintenance forces and others use the postmile markers in the field to locate specific incidents or features with reference to the postmile system.

On some stretches of road, the following prefixes may precede the mileage on a postmile marker:^[1][2]

The postmile system is the only route reference system used by Caltrans, but state highway officials have placed standard mileposts on two new freeway segments as part of an experimental program: the Mojave Bypass (State Route 58), and the State Route 180 in Fresno. The California Department of Transportation ( Caltrans) is a Government department in the U State Route 58 is an East - West Highway across the southern San Joaquin Valley, the Tehachapi Mountains, which border the State Route 180 is a State highway in California, United States, which runs through the heart of the San Joaquin Valley from Mendota Standard mileposts will eventually be added to all California freeways. In 2001 the Federal Highway Administration mandated California to add standard mileposts to all freeways, but did not set a deadline for California to come into compliance. Recently, some Caltrans districts have started to include distances in kilometers along with postmiles in their route logs, but there are no plans to add "postkilometer" markers to California's highways at this time.

States with similar reference markers

The states of Nevada and Ohio use reference markers very similar to California's postmile markers. Nevada ( is a state located in the western region of the United States of America. Ohio ( is a Midwestern state of the United States. As part of the Great Lakes region, Ohio has long been a cultural and geographical crossroads Like California, these two states record mileages through individual counties in their respective route logs. Ohio's system is nearly identical to California's with its reference markers listing the route number, 3-letter county abbreviation, and mileage through the county. The Nevada system is also similar, utilizing 2-letter county abbreviations. However, Ohio uses standard mileposts in addition to reference markers on freeways, while Nevada uses mileposts in conjunction with postmile panels on major Interstate highways only.

See also

• Milestone
• Reference marker (New York)

References