I hadn't been to Montreal for years, not since I was a student, writes Frank McDonald
Way back then, in the politically charged aftermath of Charles de Gaulle's notorious "Vive le Québec Libre" speech at the 1967 Expo, young French-speaking separatists drank St Amboise beer and fervently sang their equivalents of The Four Green Fields in the bars of Old Montreal.
But the cultural split personality that the city exhibited then is no longer so evident. Everything is in French now. All the signs and announcements on the metro are en français, as well as the names of the stations. Even the English names are rendered in French - Victoria Square is Square-Victoria, Peel Street is rue Peel, Stanley Street is rue Stanley, etc.
Montreal's main avenue was called Dorchester, but now it's Boulevard René Levesque, commemorating the founder of the Parti Québecois, which favours sovereignty for the largely French-speaking province. The terminus of one of the metro lines is Henri-Bourassa, named after the man who played a comparable role in Canadian politics to Parnell in Ireland.
Metropolitan Montreal, with a population of 3.5 million, is the second largest French-speaking city in the world after Paris. The city's native English-speaking minority (some 500,000) have their own school system, radio and TV stations, but everyone understands French and even English-speaking hotel receptionists will always greet you with "Bonjour!".
It is hard to credit that this is North America, not Normandy. But it is emphatically not the US. McDonald's bills itself as "McDonald's du Canada" and even incorporates the Canadian flag as a logo on its ubiquitous golden arches. In Montreal, the paper mats on its plastic trays are exclusively en français; its célèbres frites are French fries, naturellement.
Most bizarrely of all, the municipal administration spent 2 million Canadian dollars (€1.4 million) changing all the "STOP" signs in the city to "ARRET", just to make a linguistic point. It didn't matter that the French in France have had "STOP" signs for years; when you're on the edge, in dread of cultural absorption by a powerful neighbour, it seems to be a price worth paying.
Rue St Laurent (formerly St Lawrence Street) marks the dividing line between the east and west of Montreal. The east used to be exclusively French and the west mainly English-speaking, but now it's hard to tell. Vieux Montreal remains as French as ever, dotted with fine restaurants such as Bonaparte and Moravie that dish up French cuisine, Quebec style.
However, even Old Montreal has more than its fair share of vacant sites and parking lots. This is a common North American urban phenomenon, but has probably been aggravated in Montreal by a lack of confidence among investors. Nonetheless, there are some apartment buildings and offices under construction on key sites around the city centre.
Ten years ago, the last referendum in Quebec on secession from Canada was defeated by the narrowest of margins - 50.5 to 49.5 per cent. Obviously, there were enough francophones who understood that, if Quebec did secede, the relatively civilised entity that is Canada would be no more and that they would face an uncertain future in the world.
But one of the drawbacks of this simmering constitutional crisis, still stoked by the separatism of the Bloc Québecois, has been the flight of an estimated 500,000 English-speaking Quebecers over the past 20 years or so - most of them taking Highway 401 to Toronto. They became fed up with all the cultural concessions made to satisfy their erstwhile neighbours.
In winter, Montreal is often bitterly cold, despite being eight degrees of latitude further south than Dublin. The footpaths were covered in ice and an almost daily dusting of snow during last month's UN Climate Change Conference. I gave thanks for the Gulf Stream, but wished they would hold these annual meetings on global warming in, well, warmer places.
Montreal copes with its harsh climate - it can go as low as minus 35 0C - by having a network of underground shopping malls where people can escape from the cold. Even the gare centrale is below ground level, as is most of the city's excellent metro; its first line was built in time for the 1967 Expo, held on Île Sainte-Hélène in the Saint Lawrence River.
Redeveloped as Parc Jean-Drapeau in honour of the mayor who brought the Expo to Montreal, its main attraction (after a casino) is the former US pavilion designed by futurologist Buckminster Fuller. The shell of this sensational geodesic dome with a diameter of 80m now houses the Biosphere, a museum focusing on the river and the Great Lakes.
Whatever the outcome of next Monday's general election, it seems unthinkable that the constitutional status of Quebec will change soon. Unlike the skyscrapers of Montreal, which belch out white clouds of vapour from their roofs in winter, the separatist movement (for all of its rhetoric) may have run out of steam. "Vive la différence!" - but safely within a federal Canada.