How Airports Serve Virginia
Mark Pearson
This map displays the major airports in and around Virginia. It shows how the state can divided according to which airport is the closest as the crow flies.
The flags are a sample of 500 census tracts (of 1886 tracts total) within the state.
Some census tract flags may look like they are colored for one airport's region but are actually in another airport's region. The census tract flags are colored with which airport they are closest to as the crow flies along the surface of the earth (the Haversine distance formula). The region boundaries that are displayed on map were computed assuming assuming the earth is flat. (The lines that divide regions are a Voronoi diagram, and I couldn't find any algorithm that calculate the lines on a sphere such as the earth.) In short, although a few census tracts may look like they're mislabeled near a boundary, it's actually the boundary that is slightly wrong.
For more information, see the full report:
http://www.mark-pearson.com/airport-distances/

IAD serves 1,457,860 people in VA
Washington Dulles International Airport

RIC serves 1,333,767 people in VA
Richmond International Airport (Byrd Field)

DCA serves 1,278,929 people in VA
Ronald Reagan Washington National Airport

ORF serves 1,093,078 people in VA
Norfolk International Airport

ROA serves 900,723 people in VA
Roanoke Regional Airport (Woodrum Field)

CHO serves 727,448 people in VA
Charlottesville-Albemarle Airport

PHF serves 634,804 people in VA
Newport News/Williamsburg International Airport

TRI serves 319,960 people in VA
Tri-Cities Regional Airport (Tri-Cities Regional TN/VA)

GSO serves 155,983 people in VA
Piedmont Triad International Airport

RDU serves 64,954 people in VA
Raleigh-Durham International Airport

SBY serves 29,828 people in VA
Salisbury-Ocean City Wicomico Regional Airport

CRW serves 3,690 people in VA
Yeager Airport

dividing line

6,088 people
closest airport: CHO

5,164 people
closest airport: RIC

6,091 people
closest airport: DCA

closest airport: ORF

closest airport: PHF

closest airport: RIC

closest airport: ROA

closest airport: DCA

closest airport: IAD

closest airport: CHO

closest airport: TRI

closest airport: GSO

696 people

813 people

closest airport: SBY

closest airport: RDU

935 people

closest airport: CRW