Source: Airport Council International.
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Passenger Traffic at the World's Largest Airports, 2008

There are 3 major concentrations of airports in the world where international air traffic is articulated according to three giant platforms having an important concentration of air terminals: Eastern United States, Western Europe and Japan. The key airports of these platforms, or rather the airport cities since they count more than one airport, are New York , London and Tokyo. These poles correspond to the most important financial centers in the world.