Included with local governments are subordinate agencies, road districts, commissions, and authorities, both toll and nontoll. All States have organized county governments except Connecticut and Rhode Island. In Alabama and Maryland, the State has assumed responsibility for roads in certain counties. Counties are called parishes in Louisiana, boroughs in Alaska, municipios in Puerto Rico, and townships are known as towns in New England, New York, and Wisconsin. A municipality is a political subdivision where a municipal corporation has been established to provide general local government for a specific population concentration in a specified area.
Some counties have boundaries coextensive with cities.
Generally, these counties retain their identities only for certain administrative purposes. Because some counties are entirely urban in nature or have merged with municipalities, they are classified as municipalities. A county may also be classified as a municipality when its area consists predominantly of incorporated cities, towns, and villages. Although generally considered to be rural governments, many townships, particularly in the Northeast, serve heavily populated areas and perform the functions of a municipal government. The Federal-aid boundaries are fixed by responsible State and local officials, subject to the approval of the Secretary of Transportation.