Dorval is a city on the island of Montreal. Pierre Elliott Trudeau International Airport constitutes about 60% of the city's land, forcing all of Dorval's population to be concentrated in the southern part of the city. On January 1, 2002, the city of Dorval was dissolved and annexed to the city of Montréal. On June 20, 2004, the residents of Dorval voted to demerge from Montreal to become an independent city once again. The demerged city has been in place since January 1, 2006.