I wandered through Old Montreal and Griffintown in September 2010. Many sights were familar to me but there were others I'd never noticed before, such as the high-water mark of the flood of April 18, 1886.
I'd always thought the dividing line between Old Montreal and Griffintown was the Bonaventure Expressway. But when I was geotagging my photos, I realized that McGill Street is actually the street that separates the two districts. That makes sense, because the original western wall of Montreal ran up what is now McGill Street. The industries that developed along the Lachine Canal were located beyond the walls in Griffintown.