I know St. John's the best, obviously, and of the ones I've lived in I know Winnipeg (length of time meant I saw most of it) and Moncton (smaller size) best.
I know my way around Halifax, though I couldn't tell you from any point which direction Lower Sackville is, etc. I know my way around the core of Quebec City. I know a very small portion of the core of Montreal and Toronto, and their airports
I'm going through the list Molson shared.
My parents and I did a train trip "across Canada" from Halifax to Vancouver when I was a teen. So I've been to every province and most of their large cities, but in terms of actually "knowing" these places, I think that'd be a stretch to say. The ones I've never visited, or only visited that one time, are basically most of Canada:
Vancouver
Edmonton
Ottawa
Hamilton
Kitchener
London
Victoria
Oshawa
Windsor
Saskatoon
St. Catharine's
Regina
Kelowna
Barrie
Sherbrooke
Guelph
Kanata
Abbotsford
Etc.
On and on.
The next ones in that list with a caveat for me are Fredericton (52) and Saint John (53). When I was living in the Maritimes, I had friends in both cities and spent a handful of weekends in each. Still don't really know them, but more than, say, one teenage trip.
Charlottetown I've been to once (59), but in my 20s, so I got to see/do more.
Next one with a caveat is Cape Breton-Sydney (91). I've crossed on the ferry a few times, mostly as a child. I don't know if we ever went into Sydney proper or just North Sydney, onto the highway, and on to Halifax.
In this list... I'd put Galway and Dublin in the same range for me as Quebec City. All of the other places I've been were one visit only. Most recent was Malaga, Spain - I could definitely find my way anywhere from Fuengirola to the downtown core, but I obviously don't know it. Don't even speak the language.