The Mirabel Airport, once intended to be the world's largest, now stands as a symbol of unfulfilled potential and isolation. In 1975, the Canadian government expropriated nearly 40,000 hectares of agricultural land in the northwest of Montreal, displacing around 11,000 people in what remains the largest land seizure in Canadian history. This area was larger than the city of Montreal and much bigger than the city limits of Paris. The goal was to build an airport that could handle up to 40 million passengers annually by the year 2000, at a time when air travel was expected to grow indefinitely. The airport was officially opened by then-Prime Minister Pierre Elliott Trudeau on October 4, 1975, after five years of construction and an investment of 500 million dollars. However, a crucial part of the plan—a high-speed rail link connecting Mirabel to Montreal—was never completed. Without this link, travelers had to drive about 50 kilometers from downtown Montreal to reach the airport, making it far less convenient than the nearby Dorval Airport, which was closer to the city center. The failure to build the rail link, combined with economic challenges in the 1970s such as the oil crisis, which slowed global air travel, made the original vision of Mirabel's success seem outdated. Meanwhile, the airport in Toronto was growing in importance and attracting more international traffic. As a result, airlines and travelers increasingly chose Dorval over Mirabel, despite its smaller size and less modern facilities. In 1997, Montreal Airports officially moved regular international flights to Dorval, signaling the commercial failure of Mirabel. The last passenger flight departed on October 31, 2004, just 29 years after the airport's inauguration. The terminal was later demolished between 2014 and 2016. Today, the site is no longer a bustling airport but has been repurposed as an industrial and logistics hub, serving air freight and parts of the Quebec aerospace industry. While the runways still function, their use is vastly different from the original vision of the 1970s. A group of families who were displaced by the expropriation continues to seek funding to create a memorial site, featuring a sculpture by artist Armand Vaillancourt. This would honor the thousands of people affected by the project, which was built on the promise of the future but never fully realized. The story of Mirabel is not just about an overambitious airport, but about a vision of infrastructure that ultimately failed due to a lack of key components, leading to its isolation and eventual decline.