what is airtrain jfk?
An elevated people mover system and airport rail link serving John F. Kennedy International Airport
AirTrain JFK
AirTrain JFK is an elevated people mover system and airport rail link serving John F. Kennedy International Airport (JFK Airport) in New York City. 
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AirTrain JFK [SEP] Introduction
AirTrain JFK is an elevated people mover system and airport rail link serving John F. Kennedy International Airport (JFK Airport) in New York City. The driverless system operates 24/7 and consists of three lines and ten stations within the New York City borough of Queens. It connects the airport's terminals with the New York City Subway in the Howard Beach neighborhood of Queens, and with the Long Island Rail Road and subway in the Jamaica neighborhood. Bombardier Transportation operates AirTrain JFK under contract to the airport's operator, the Port Authority of New York and New Jersey. A railroad link to JFK Airport was first recommended in 1968.