A county seat is a term for an administrative center for a county, primarily used in the United States. In the Northeast United States, the statutory term often is shire town, but colloquially county seat is the term in use there. Louisiana uses parishes instead of counties, and the administrative center is a "parish seat." Alaska is organized into "boroughs," which are large districts, and the administrative center is known as a "borough seat." Boroughs typically provide fewer local services than most counties, as the state government provides more services directly. About half of Alaska is part of the Unorganized Borough, a discontinuous region the state government administers directly. Some of Alaska's boroughs share geographical and administrative boundaries with cities; these are known as unified city-boroughs and result in some of Alaska's cities ranking among the geographically largest cities in the world.
United States counties, as in England and Canada, function as administrative divisions of a state and have no sovereign jurisdiction of their own. Counties administer state or provincial law at the local level as part of the decentralization of state/provincial authority. In many U.S. states, state government is further decentralized by dividing counties into townships, to provide local government services to residents of the county who do not live in incorporated cities or towns.
A county seat is usually, but not always, an incorporated municipality. The exceptions include, but are not limited to, the county seats of counties that have no incorporated municipalities within their borders, such as Arlington County, Virginia, and Baltimore County and Howard County, Maryland. (Ellicott City, the county seat of Howard County, is the largest unincorporated county seat in the U.S., followed by Towson, the county seat of Baltimore County.) The county courthouse and county administration are usually located in the county seat, but some functions may also be conducted in other parts of the county, especially if it is geographically large.
Most counties have only one county seat. However, some counties in Alabama, Arkansas, Iowa, Kentucky, Massachusetts, Mississippi, New Hampshire, New York, and Vermont have two or more county seats, usually located on opposite sides of the county. An example is Harrison County, Mississippi, which lists both Biloxi and Gulfport as county seats. The practice of multiple county seat towns dates from the days when travel was difficult. There have been few efforts to eliminate the two-seat arrangement since a county seat is a source of pride (and jobs) for the towns involved. Connecticut and Rhode Island have no county level of government and thus no county seats. Vermont has its shire towns, but no county government to speak of, consisting only of a Superior Court and Sheriff (as an officer of the court). Massachusetts has abolished a number of its counties and the state now operates the registries of deeds and sheriff's offices in those districts. Two counties in South Dakota, Shannon County, and Todd County, have their county seat and government services centered in a neighboring county. Their county-level services are provided by Fall River County and Tripp County, respectively.
Though New York is a single city, it stretches across five counties. Often referred to as the boroughs of New York, each is also a separate geographic (unorganized) county, with city-sponsored borough officials. The five counties that compose New York City are Bronx County (the Bronx), Kings County (Brooklyn), New York County (Manhattan), Queens County (Queens), and Richmond County (Staten Island). The "county seats" of Richmond and Queens County are effectively neighborhoods, though they correspond roughly to the location of borough hall.
In Virginia, there are (since 2001) 39 independent cities, which are legally distinct from the counties that surround them. An independent city interacts with the commonwealth (state) government directly whereas towns, the only other type of municipal government authority in Virginia, do so through the county government apparatus. In many of Virginia's counties, the county government offices are located within the independent cities of their neighboring counties. Also, for certain statistical purposes, some independent cities are considered part of the county from which they separated. For example, the City of Fairfax is separate from Fairfax County, the county's offices lie within the city, and the city is combined with Fairfax County statistically.
Similarly, the city of Baltimore, Maryland is also an independent city, and much like Fairfax, surrounded on three sides by a county of the same name. However, unlike Fairfax, "Baltimore City", as it is officially known, is not politically or statistically related with surrounding Baltimore County. Besides Baltimore City and the independent cities of Virginia, there are only two other independent cities in the United States: St. Louis, Missouri; and Carson City, Nevada.
