Where Montreal’s boroughs of Rosemont–La Petite-Patrie and Plateau-Mont-Royal meet lies the intersection of Rue d'Iberville and Boulevard Saint-Joseph. Between 1992 and 2012, more than 250 serious vehicular accidents were reported there, at "Tunnel de la Mort”.

Retaining walls and railway overpasses form an artificial box canyon of sorts around the two streets, each of which narrows as it approaches the tunnel. The walls and overpasses reduce visibility significantly. Meanwhile, as they approach the intersection, Rue d'Iberville loses half of its previous four lanes and Boulevard Saint-Joseph loses a third of its six, as the roadbeds narrow.

In 2001, Guy Chevrette—minister of transportation at that time—said that the intersection was too dangerous to enforce traffic laws by posting a police cruiser near the intersection. Flashing yellow signals were installed near the intersection to warn motorists of the hazard, all left turns were banned.

Beginning on April 4, 2002, roadwork began to make the intersection safer. One of the railroad overpasses was torn down, improving visibility. Demolition of the other overpasses has been discussed, but the Canadian Pacific Railway uses both of the remaining two for one of its major operations. Quebec’s Ministry of Transportation indicated that the entire ersatz tunnel would be redesigned and rebuilt by July 2010, but as late as August, 2017, it still existed.

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