Boasting a 549m span suspended between its two main pillars, the Quebec Bridge straddles the St Lawrence River and at the time of its construction was the longest cantilever bridge in the world. The project turned into a nightmare with the bridge collapsing in 1907 and, in 1916, the central span plunging into the river just as it was being installed. Opened to rail travel in 1917, it has been used by cars since 1929.