Montréal-Mirabel International Airport (or Montréal International (Mirabel) Airport) (IATA: YMX, ICAO: CYMX), originally called Montréal International Airport and widely known simply as Mirabel, is a cargo airport located in Mirabel, Quebec, Canada, 21 nautical miles (39 km; 24 mi) northwest of Montreal and opened October 4, 1975. It was the largest airport in the World in terms of surface area ever envisioned, with a planned area of 39,660 hectares (396.6 sq km). The King Fahd International Airport in Saudi Arabia, which was completed in 1999, surpassed its surface area.
In 1989, 81,000 acres (32,780 ha) of the 98,000 acres (39,660 ha) were deeded back to their owners.The predominant role of the airport is cargo flights but it is also home to MEDEVACs and general aviation flights as well as being a manufacturing base for Bombardier Aerospace, where final assembly of regional jet (CRJ700, CRJ900 and CRJ1000) aircraft is conducted. The former passenger terminal apron is now a racing course.
It was intended to replace the existing Dorval Airport as the eastern air gateway to Canada; from 1975 to 1997, all international flights to/from Montreal were required to use Mirabel. However, Mirabel's distant location and lack of transport links made it unpopular with airlines and travellers. Moreover, Montréal's economic decline relative to Toronto kept passenger volumes from rising to the levels originally anticipated. And so Dorval Airport not only remained viable but resumed handling overseas flights. Eventually, Mirabel was relegated to the role of a cargo airport. Initially a source of pride, the airport became an embarrassment, widely regarded in Canada as being a boondoggle and a white elephant. Ironically, the Dorval Airport was renamed Montréal-Pierre Elliott Trudeau International Airport after the Canadian Prime Minister, Pierre Elliot Trudeau, whose government spearheaded the Mirabel project to replace Dorval.
The airport is classified as an airport of entry by NAV CANADA and is staffed by the Canada Border Services Agency. CBSA claims that its officers at this airport currently can handle general aviation aircraft only with no more than 15 passengers but larger aircraft have been serviced.
It is one of two airports in Canada with sufficient right-of-way that can be expanded to accommodate 50 million passengers per year, the other being Toronto Pearson International Airport, though a lack of traffic meant that Mirabel was never expanded beyond its first phase. It is one of only two non-capital airports with fewer than 200,000 passengers a year to be part of the National Airports System.The airport is 55 km (34 mi) northwest of Downtown Montreal and 47 km (29 mi) northwest of Trudeau Airport.