A county highway (also county road or county route; usually abbreviated CH or CR) is a road in the United States and in the Canadian province of Ontario that is designated and/or maintained by the county highway department. Route numbering can be determined by each county alone, by mutual agreement among counties, or by a statewide pattern.
Any county-maintained road, whether or not it is given a signed number, can be called a county road. Depending on the state or province and county, these roads can be named after local geographic features, communities, or people and/or be assigned a name determined by a standardized grid reference; for example: "East 2000 Road" would be a north–south road running 20 blocks/miles/km east of the designated zero point. Many other systems are also used; some counties rather arbitrarily assign numbers to all maintained roads, but do not sign them at all or only sign them on standard street sign blades.
County roads and highways vary greatly in design standards, funding and regularity of maintenance. Some county highways in urban areas are freeways or expressways. County roads that link communities or serve residential areas are often indistinguishable from state highways or residential streets. In rural areas, many county roads carry very little traffic; these roads are maintained less frequently. They may be in poor condition (if they are paved) or not paved at all. In remote areas, county roads are made of sand, gravel, or graded earth, seeing only occasional foot, equestrian, and four wheel drive traffic. Some states, such as Wisconsin, use county highways in great numbers, linking major highways and cities or towns to each other. Wisconsin also maintains a Rustic Road system where county and local routes are purposefully maintained as dirt or gravel roads in order to not interfere with natural scenery and to preserve them in their past state.
In England and Wales, the term 'County Road' means a road for which the county council is the highway authority (s.29 Local Government Act 1929).
County highway shields are usually a yellow-on-blue pentagon (the Manual on Uniform Traffic Control Devices standard pattern), a black-on-white rectangle, or black text on a white rectangle (largely older signs). Some states, like Virginia and North Carolina, have no county highways in most of their counties; the state government maintains all roads in unincorporated areas. Others, like Connecticut, have no county routes because there is no government at the county level. Alaska's county-equivalent boroughs maintain roads in unincorporated areas but none are numbered; Louisiana's county equivalents are parishes, and, accordingly, have parish routes.