Source: Airports Council International. Note: airports having traffic above 4 million passengers.
Passenger air travel is linked with the level of economic development and the structure of the regional urban system. The world’s air traffic is articulated in three major concentrations of airports: North America, Western Europe, and East Asia. The key airports of these platforms, or rather the main airport cities since they count more than one airport, are New York, London, and Tokyo. They correspond to the world’s most prominent cities and financial centers. Yet, this supremacy is being challenged by new hubs of activity such as Beijing and Dubai. Thus, there is a direct relationship between the level of air passenger traffic and the primacy of a city in the world urban system. In some cases, the level of passenger activity is related to a pronounced touristic or resort function of an area (e.g. Las Vegas, Orlando, Cancun, Venice, Palma de Mallorca).
Global air traffic has a high concentration level, with the 25 largest airports accounting for 20% of the traffic. Large airport terminals also see a substantial concentration of related activities such as distribution centers, just-in-time manufacturers, office parks, hotels, restaurants, and convention centers. Airport traffic figures must be considered cautiously, as a passenger can be counted several times depending on a trip sequence. For instance, a passenger flying roundtrip between New York and Copenhagen by transiting through Amsterdam would count for a total of 8 passenger movements for the respective airports; 2 for New York and Copenhagen (arriving and departing) and 4 for Amsterdam (arriving and departing for both inbound and outbound trips).