S: Small hub that accounts for between 0.05% and 0.25% of total U.S.M: Medium hub that accounts for between 0.25% and 1% of total U.S.L: Large hub that accounts for at least 1% of total U.S.Each primary airport is sub-classified by the FAA as one of the following four 'hub' types ( s): P- s: Commercial service – primary are publicly owned airports that receive scheduled passenger service and have more than 10,000 passenger boardings ( enplanements) each year.Role – One of four FAA airport categories, as per the 2023–2027 National Plan of Integrated Airport Systems (NPIAS) report released October 2022:.Those shown in bold indicate the airport has scheduled passenger service on commercial airlines. Airport name – The official airport name.ICAO – The location indicator assigned by the International Civil Aviation Organization (ICAO).Those that do not match the FAA code are shown in bold. IATA – The airport code assigned by the International Air Transport Association (IATA).FAA – The location identifier assigned by the Federal Aviation Administration (FAA).

It is not meant to be a complete list of cities served, which can be found in or added to each airport's Wikipedia article. This is not always the actual location since some airports are located in smaller towns outside of the city they serve. City served – The city generally associated with the airport, as per the airport's master record with the Federal Aviation Administration.This list contains the following information:

Nearest airport to cedar city utah