Montreal is an island city divided into an ever-shifting number of
boroughs (arrondissements) - a fact that is all but irrelevant
for most city visitors because, arguably, only two of those boroughs
(Ville-Marie and Plateau Mont-Royal)
contain absolute must-visit destinations.
The situation is further muddled by the fact that the political boundaries of
Montreal-the-city do not match the geographical boundaries of Montreal-the-island: there are on-island municipalities that are not considered part of Montreal - at least, not formally. Most of those are suburban in character and their exact administrative status is rather a moot point, but some, like Westmount, are located virtually blocks away from the downtown core.