In most of the United States, counties are the political subdivisions of a state. The city, town, or populated place that houses county government is known as the seat of its respective county. Generally, the county legislature, county courthouse, sheriff's department headquarters, hall of records, jail and correctional facility are located in the county seat, though some functions (such as highway maintenance, which usually requires a large garage for vehicles, along with asphalt and salt storage facilities) may also be located or conducted in other parts of the county, especially if it is geographically large.
A county seat is usually, but not always, an incorporated municipality. The exceptions include the county seats of counties that have no incorporated municipalities within their borders, such as Arlington County, Virginia (where the county seat is the entire county). Ellicott City, the county seat of Howard County, is the largest unincorporated county seat in the United States, followed by Towson, the county seat of Baltimore County, Maryland. Likewise, some county seats may not be incorporated in their own right, but are located within incorporated municipalities. For example, Cape May Court House, New Jersey, though unincorporated, is a section of Middle Township, an incorporated municipality. In some of the colonial states, county seats include or formerly included "Court House" as part of their name, (e.g. Spotsylvania Courthouse, Virginia).