On your way from Montreal to Toronto or vice versa, I highly recommend a sojourn -- of at least a…read moreday -- in the beautiful not-so-little hamlet of Kingston. While this port town will never be mistaken for its it more popular, more sunny, more reggaed, more Rastifaried, more spring-breaked Jamaican counterpart, it's definitely a gem worth visiting.
Kingston is a UNESCO World Heritage Destination found on the convergence of Lake Ontario and the St. Lawrence River. One of its most popular activities is boating ... either staying on a house on the water or if a true tourist like myself, taking a ship through the Thousand Islands. While there are countless options, I have recommended in another review (https://urlzs.com/Swzxt) hopping aboard the Island Belle by "Kingston 1000 Islands Cruises" on their Discovery Cruise. Whether them, St. Lawrence Cruise Lines, Kingston Trolley, or other providers, I imagine it's hard to go wrong as the Islands are stunning.
I recommend starting at the Kingston Visitor Information Centre (which I have also reviewed here: https://urlzs.com/DCcnD). They can get your visit on the right track (and can get you tickets to things like the cruises here.
However, there's a lot to see right there by the Visitor Information Centre: City Hall across the street, Confederation Park and Fountain behind it, the BIG LETTERS for Kingston (with the "I" absent so people can stand there :), and the famed Canadian Pacific steam train, "Spirit of Sir John A."
We came in on a Sunday. While I must warn that on Sunday some businesses are closed, there is still plenty to do. On our first visit to the big K on a Sunday, there was the Kingston Sunday Antique Market. Some cool stuff ... it's behind City Hall on King St, between Market & Brock streets (April - October, weather permitting).
I recommend getting the "K-Pass", which includes that Kingston 1000 Islands Cruises as well as the Kingston Trolley Tour. Other sights and attractions are included, such as Fort Henry, SanTur Brewing, The Kingston Pen, Ahoy Bike Rentals, "The Haunted Walk" and a whole bunch of other things I can't remember.
Don't forget there are several ways to get to Kingston, including VIA Rail that stops here on the way back and forth betwixt Montreal and Toronto.
You really haven't seen Ontario until you've seen Kingston. I can't wait to return!