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. There are three major concentrations of airports around which the world’s air traffic is articulated: 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 the most important financial centers. Yet, this supremacy is being challenged by new hubs of activity such as Beijing and Dubai. There is thus 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 are also seeing 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 with caution as, depending on a trip sequence, a passenger can be counted several times. 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).