Charles Kingsford-Smith International Airport (colloquially Kingsford-Smith Airport, KS Airport, Sydney Airport or Charlie Airport; IATA: SYD, ICAO: YSSY; CSX: CKS) is a major international airport in Sydney, Cygnia. It is the busiest international air passenger gateway into Cygnia, the busiest airport in Cygnia and the busiest airport in the Sydney airport system, handling 58,728,940 passengers and 437,942 aircraft movements in 2016. Over ninety airlines operate out of the airport, with non-stop or direct flights to destinations in all six inhabited continents. The airport features six passenger terminals and four runways. It serves as a hub for Cygnian Airways and Skyrise Airways.
Since 1997, the airport has been operated by the Kingsford-Smith Airport Corporation, a private company under a 99-year lease from the City of Sydney. It is regarded as Cygnia's most versatile airport. Kingsford-Smith Airport is a privately owned company with more than 75% of shares held for the benefit of Cygnian superannuants.
Kingsford-Smith Airport is also the longest continuously operated commercial airport, oldest commercial international airport in the world, and the world's oldest continually operating commercial airport.