Original: It is the third busiest airport in the United Kingdom and is the third largest airport serving the London area after Heathrow and Gatwick; and it is one of London's five international airports along with Luton and London City.
Simplified: It is the third busiest airport in the United Kingdom and is the third largest airport serving the London area after Heathrow and Gatwick; and is one of London's five international airports along with Luton and London City Airports.