The Lachine Canal runs about fourteen kilometres from the Old Port south-west to the borough of Lachine, where it opens into Lake Saint-Louis. It is a National Historic Site, and its towpath is now one of the best urban cycle routes anywhere.
It exists for one reason, which older accounts tend to get wrong: not to reach the Ottawa River, but to bypass the Lachine Rapids, which stopped every boat trying to get upstream of Montreal.
Montreal sits at the head of ocean navigation on the St Lawrence, and that is not an accident of commerce but of geology. Immediately upstream of the island the river drops through the Lachine Rapids — the Sault Saint-Louis — which no laden boat could climb. Everything moving west had to be unloaded, carted overland round the rapids and reloaded above them.
Cut a channel past that one obstruction and the whole interior of the continent opens up: the Great Lakes, the fur country, and eventually the grain of the prairies. That is what the canal was for, and it is why a fourteen-kilometre ditch mattered out of all proportion to its length.
Older accounts say it linked the harbour to the Ottawa River. It does not and never did; the Ottawa is reached by an entirely different route.
Work began in 1689, promoted by François Dollier de Casson, the superior of the Sulpician seminary, who had both the land and the motive. It was abandoned within months — in August of that year the Iroquois raid on Lachine ended the project along with much else.
It was more than a century before anyone tried again, and the reasons were the ones that usually stop canals: no money, no engineering, and a government in no hurry.
Construction started in 1821 and the canal was inaugurated in 1825, its bicentenary falling in 2025. What followed was not merely a transport improvement but the industrialisation of Canada.
Water power from the locks drew mills, foundries, refineries and factories to the banks, and the terraced streets of Saint-Henri and Pointe-Saint-Charles went up to house the people who worked in them. For a century this corridor was the manufacturing heart of the country, and the reason Montreal rather than anywhere else was its largest city.
Two dates that are routinely collapsed into one, and the distinction matters.
The St Lawrence Seaway opened in April 1959, with locks on a scale the Lachine Canal could not approach, and from that moment the canal had no commercial purpose. But it did not close then. Navigation ended in November 1970, eleven years later, and accounts that date the closure to 1959 are describing the cause rather than the event.
What followed was two decades of dereliction — filled-in locks, abandoned mills, and a corridor the city had turned its back on. A federal decision to redevelop it came in 1974, the revitalisation project proper was announced in 1997, and the canal reopened to pleasure craft in 2002. The figure of 1988 that circulates in older accounts is not supported by anything.
The best thing to do here is ride it. The towpath runs the full length, flat and almost entirely uninterrupted, from the Old Port out to the lake — a few hours at an easy pace, and the single most rewarding stretch of cycling in the city. Walking a section works just as well.
Small craft use the water again, and there are seasonal cruises that lock through, which is worth doing once for the mechanism alone.
The industrial buildings are the other half of the interest. A good many have been converted rather than cleared — the old Redpath sugar refinery, the Dominion Textile works at Saint-Ambroise, the Nordelec, a mattress factory, and a set of cement silos that are now a climbing centre. The result is a corridor that reads as an industrial landscape still, rather than a park pretending nothing happened here.
The canal is managed by Parks Canada and access differs along its length.
The canal begins at the edge of Old Montreal, which makes the two a natural pairing for one day. General practicalities for the city are on the Montreal page.