The Quebec City–Windsor Corridor is the most densely populated and heavily industrialized region of Canada. As its name suggests, the region extends between Quebec City in the northeast and Windsor, Ontario in the southwest, spanning . With more than 18 million people, it contains over half of the country's population and three of Canada's four largest metropolitan areas according to the 2011 Census. In its relative importance to the Canada's economic and political infrastructure, it has many similarities to the Northeast megalopolis in the United States. The name was first popularized by Via Rail, which runs frequent passenger rail service in the Quebec City–Windsor Corridor on its route named "The Corridor".