The Plateau-Mont-Royal takes its name from its location on relatively flat terrain north of Sherbrooke Street and downtown, and east of Mont-Royal. The borough is bordered to the north and north-east by the Canadian Pacific Railway tracks; to the west by Hutchison (north of Mount Royal Avenue), Park Avenue (between Mount Royal and Pine Avenue) and University Street (south of Pine Avenue); and to the south by Sherbrooke Street. It is the most densely populated borough in Canada, with 101,054 people living in an 8.1 square kilometre area.
There is a difference between the borough, Plateau-Mont-Royal—a political division of the City of Montreal—and the neighbourhood referred to as "the Plateau". The borough includes not only the Plateau proper, but also the neighbourhoods of Mile End (bounded by Avenue du Mont-Royal to the south and the Avenue Henri-Julien to the east) and Milton Park (bounded by University, Sherbrooke, Saint-Laurent and Pine). Both neighbourhoods are generally considered distinct from the Plateau.