From Wikipedia : Luton Airport Parkway station is on the Midland Main Line in England, serving south Luton and Luton Airport in Bedfordshire. The station is situated in Luton's Park Town district, being 29.27 miles (47.11 km) from London St Pancras between Harpenden to the south and Luton to the north. Its three-letter station code is LTN, also the IATA code for the airport.