Montreal Mirabel International Airport (IATA: YMX, ICAO: CYMX) was built in the early 1970s as a massive infrastructure project intended to replace Dorval Airport as Montreal's primary international gateway. Opened in 1975, it was one of the largest airports in the world by land area, covering approximately 400 square kilometers, but it never achieved the passenger volumes its planners envisioned due to poor public transit links, distance from Montreal, and airline resistance. Passenger services were gradually wound down, with the last scheduled commercial passenger flights departing in 2004. The airport was subsequently repurposed and today operates primarily as a cargo hub and aerospace manufacturing and maintenance center, hosting major aerospace firms including Bombardier and Bell Helicopter Textron. Mirabel remains an important facility for the Canadian aviation and aerospace industry, with the Aéroports de Montréal authority managing the site. Its passenger terminal was demolished in 2014, symbolizing the definitive end of its commercial passenger aviation era.