Ottawa/Macdonald-Cartier International Airport or Macdonald-Cartier International Airport (L'aéroport international Macdonald-Cartier in French), (IATA: YOW, ICAO: CYOW) in Ottawa, Ontario, Canada is named after Sirs John A. Macdonald and George-Étienne Cartier. Located in Riverside South, 5.5 NM (10.2 km; 6.3 mi) south of downtown Ottawa, it is Canada's sixth busiest airport by airline passenger traffic and by aircraft movements, with 4,473,894 passengers and 172,115 aircraft movements in 2010. The airport is an Air Canada Express and Air Canada focus city and the home base for First Air. The airport is classified as an airport of entry by NAV CANADA and is staffed by the Canada Border Services Agency. The airport is one of eight Canadian airports that have United States border preclearance facilities. The airport was formerly a military base known as CFB Ottawa South/CFB Uplands.
The airport was originally opened at Uplands on a high plateau (then) south of Ottawa by the Ottawa Flying Club, which still operates from the field. During World War II, when it was known as Uplands, the airport hosted No. 2 Service Flying Training School for the British Commonwealth Air Training Plan, providing advanced pilot training in Harvard and Yale aircraft.