Due to its proximity to the Principality of Monaco, it also serves as the city-state's airport, with helicopter service linking the principality and airport. Some airlines market Monaco as a destination via Nice Airport. The airport covers an area of over 3.70 km2, with 2.70 km2 used by its two parallel runways and the two passenger terminals and freight terminal. The airport's theoretical capacity is 13 million annual passengers and 52 movements (26 landings) per hour. The two airport terminals are linked by courtesy shuttle buses that also connect the car parks with the terminals.