KLM Airlines operates at the Main Terminal of Athens International Airport (ATH).Athens International Airport’s Main Terminal is home to KLM Airlines ATH Terminal .Convenient check-in counters, cozy waiting lounges, and a variety of eating and retail alternatives are available to travelers. Traveling with KLM at ATH is made easy and pleasurable by the terminal’s effective services and amenities, which guarantee a flawless experience for both arrivals and departures.