Anne Arundel County forms part of the Baltimore-Washington metropolitan area. The center of population of Maryland is located on the county line between Anne Arundel County and Howard County, in the unincorporated town of Jessup.
As of the census of 2000, there were 489,656 people, 178,670 households, and 129,178 families residing in the county. The population density was 1,177 people per square mile (455/km²). There were 186,937 housing units at an average density of 449 per square mile (174/km²). The racial makeup of the county was 81.24% White, 13.57% Black or African American, 0.30% Native American, 2.29% Asian, 0.06% Pacific Islander, 0.85% from other races, and 1.69% from two or more races. 2.63% of the population were Hispanic or Latino of any race. 17.7% were of German, 13.1% Irish, 10.5% English, 8.1% United States or American and 7.0% Italian ancestry according to Census 2000.
There were 178,670 households out of which 34.90% had children under the age of 18 living with them, 57.20% were married couples living together, 11.10% had a female householder with no husband present, and 27.70% were non-families. 21.30% of all households were made up of individuals and 6.40% had someone living alone who was 65 years of age or older. The average household size was 2.65 and the average family size was 3.09.
In the county the population was spread out with 25.20% under the age of 18, 8.10% from 18 to 24, 32.80% from 25 to 44, 23.90% from 45 to 64, and 10.00% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 99.10 males. For every 100 females age 18 and over, there were 97.10 males.
The median income for a household in the county was $61,768, and the median income for a family was $69,019 (these figures had risen to $79,294 and $91,071 respectively as of a 2007 estimate). Males had a median income of $43,747 versus $32,348 for females. The per capita income for the county was $27,578. About 3.60% of families and 5.10% of the population were below the poverty line, including 6.30% of those under age 18 and 5.80% of those age 65 or over.
This population history of Anne Arundel County from the U.S. Census Bureau compares the population of Anne Arundel County to those of the other 23 Maryland counties and Baltimore City.
Anne Arundel county is the home of Baltimore-Washington International Thurgood Marshall Airport, commonly referred to as BWI. BWI serves as the main airport for greater Baltimore. It is also an increasingly popular alternative airport to residents of the Washington, D.C., area. BWI is an East Coast hub for Southwest Airlines, meaning that direct flights are available between BWI and much of the country.
The southern portion of the Maryland Transit Administration's Light Rail system, connecting downtown Baltimore with BWI, runs through part of Anne Arundel County.
The county also has multiple stops on the MARC commuter rail service, including a stop at BWI Rail station, located near BWI Airport. Amtrak trains also stop at BWI's train station.
Additionally, the Laurel-based Connect-a-ride system operates two routes in the western portion of the county; including Severn, Arundel Mills, Maryland City, Glen Burnie, Hanover, and Odenton. Howard County's Howard Transit Silver route serves Arundel Mills shopping mall and BWI Thurgood Marshall Airport.
The county is served by one main-line interstate, Interstate 97, which is the country's only main-line interstate highway contained completely within a single county. Interstate 695, the McKeldin Beltway (commonly known as the Baltimore Beltway), runs through the northern part of the county. Interstate 895, the Harbor Tunnel Thruway, runs through the county towards the Baltimore Harbor Tunnel. Interstate 195, a spur off of Interstate 95, serves BWI Airport, while Maryland State Highway 100 runs east-west through the northern part of the county.
Interstate 595 also runs through central Anne Arundel County. This highway, however, is not signed. It is referred to by its more common names, US 50 and U.S. Route 301.
The Chesapeake Bay Bridge crosses the Chesapeake Bay from the county; it connects the Western Shore with the Eastern Shore in Queen Anne's County.