Area code 304 covers the entirety of West Virginia with the overlay of the 681 area code. AT&T introduced area code 304 as part of the North American Numbering Plan in 1947. The largest cities in area code 304 are Charleston, Huntington and Parkersburg.
Area code 304 was the sole area code for West Virginia until 2009 when the North American Numbering Plan added the 681 area code. As in other districts with overlay area codes, West Virginians must now use 10-digit dialing and dial area codes even before local calls.
AT&T and Bell Laboratories developed and introduced area codes during the 1940s to ease the process of long-distance calling. Along with the United States, the North American Numbering Plan covers Canada and many island nations, including Bermuda, Barbados and Jamaica.
Approximately 1.9 million people live in West Virginia, as of 2015. Its capital, Charleston, has a population of 51,000. European pioneers first settled in the area during the early 1700s. The state was part of Virginia before the Civil War, at which point 40 western counties opposed to secession formed their own government. The state is known for its production of coal and other important natural resources including oil, natural gas and forestry products. West Virginia is mountainous and attracts tourists to its nine state forests and two national parks.