How Airports Serve Oregon
Mark Pearson
This map displays the major airports in and around Oregon. 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 826 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/

PDX serves 2,187,394 people in OR
Portland International Airport

EUG serves 812,388 people in OR
Eugene Airport (Mahlon Sweet Field)

MFR serves 433,406 people in OR
Rogue Valley International-Medford Airport

RDM serves 226,609 people in OR
Redmond Municipal Airport (Roberts Field)

PSC serves 124,450 people in OR
Tri-Cities Airport

BOI serves 46,827 people in OR
Boise Airport (Boise Air Terminal) (Gowen Field)

dividing line

1,977 people
closest airport: PDX

3,634 people
closest airport: PDX

3,589 people
closest airport: EUG

closest airport: MFR

closest airport: PDX

closest airport: BOI

closest airport: EUG

closest airport: RDM

closest airport: PSC

8 people