The Athens Metro is a rapid-transit system in Greece that serves the Athens urban area. The Athens Metro consists of three operational lines totaling 91.7 kilometers (57.0 mi) and 66 stations – Line 1 in green, Line 2 in red, and Line 3 in blue – the metro brings life to residents and visitors alike. It serves as a transit line, providing a fast and efficient means of travel. STASY owns and operates 62 of the 66 stations: three other stations (Palini, Piania-Kantza and Koropi) belong to GAIAOSE and Athens Airport station belongs to the operator of Athens International Airport. The system has five interchanges, Attiki, Monastiraki, Omonia, Piraeus and Syntagma, allowing all three to interchange with each other at least once. Each line also has at least one connection to the Athens Suburban Railway and the Athens Tram.