County (United States) - Cities and Counties

Cities and Counties

In general, cities, towns, and other municipal governments almost always occupy a smaller area than the county which contains them, and they reside only in that county (that is, they are prohibited from annexing territory in more than one county). However, there are exceptions:

1. A city and its containing county may be merged to form a consolidated city-county, which is considered both a city and a county under state law. Examples include Philadelphia; New Orleans; Denver; Broomfield, Colorado; San Francisco; Indianapolis; Jacksonville; and Nashville. Similarly, some of Alaska's boroughs have merged with their principal cities, creating unified city-boroughs. Such consolidations and mergers have resulted in creating cities that rank among the geographically largest cities in the world, though often with population densities far below that of most urban areas.
2. A city may extend across county boundaries in several states where the state constitution or state law authorizes it.

• In some states, this practice is routine, as expanding cities simply annex land in adjoining counties. For example, Aurora, Illinois, once confined to Kane County, has spread to a total of four counties.
• In the case of New York City, the modern city was actually established as covering five counties in their entirety, and today each of these is coextensive with one of the five boroughs of the city: Manhattan (New York County), The Bronx (Bronx County), Queens (Queens County), Brooklyn (Kings County) and Staten Island (Richmond County).