Quebec City might just have the most unique culture of any North American city, certainly the most unique among the ones I’ve been to.
Not only is the architecture unique (i think it’s the last remaining fortified city in North America and there are old structural stone buildings everywhere), it is primarily french speaking (even more than the larger city of Montreal a few hours away), and the narrow cobblestone streets make it feel just as walkable as a European city.
Beyond that, the province of Quebec really feels like it’s a separate country (way more Quebec flags than Canadian flags), and the festivals and events they host in QC feel distinctly different.
As an example, they host the only UCI world tour cycling race in North America each year, and in the winter they host the world’s largest Winter Festival.
Definitely worth a trip if you’ve never been.