Two of my favorite spots in Canada are St. John, New Brunswick, and Halifax, Nova Scotia, both downtown areas with excellent maritime museums.
St John is a very interesting sea town and the city where they have the reversing river. Every time the 40' tide changes, the river changes direction. It is full of rocks and rapids, both ways, so you could start out of a raft or kayak in downtown, ride "up river" for 6 hours and then ride back to where you started! I had a little trouble parking my RV, but called ahead and found a nice lot about 4 blocks away. Good restaurants and shops downtown, as well, as an excellent museum. (http://grandmajjb.blogspot.com/2015/09/92-saint-john-new-brunswick-reversing.html)
Halifax is a terrific city with a fantastic Harbour Walk in the downtown area. It took a little navigating, but I found a huge parking lot on a Sunday right along the river. I spent a couple of hours at the Maritime museum and then walking around the harbor area and having a lobster roll outdoors. Halifax is where they took the dead and the survivors from the Titanic, so they also have a substantial exhibit there and a graveyard. http://grandmajjb.blogspot.com/2015/09/915-halifax-and-maritime-museum.html
And don't miss Peggy's Cove and the colorful Lunenburg on Nova Scotia! Best NOT to visit these popular Maritime places in the fall, however, as the cruise ship disgorge thousands of passengers to those places in September!