Canadian cities worth visiting would have to include, in the Eastern part of the Country, Halifax, Nova Scotia, Charlottetown, Prince Edward Island, and any city in Newfoundland. You will feel the friendliness of the people rubbing off on you the longer you stay, and the seafood is to die for, and priced economically, with heaping helpings. Beautiful seascape vistas, whale watching and deep-sea fishing, along with the always invigorating lighthouse tours are must sees for the eastern Provinces. Quebec City with it's old-world charm and fortress-like structure, cobblestone streets barely wide enough for a large vehicle, and patios to eat, drink and be merry on almost every block is one of those "have to see before you die" type of Cities. Montreal is a must visit city for their renowned night-life, concerts, parks the Arboretum, Casino and sports teams.
Toronto, where you can stroll around the beaches during the day, and then visit the busiest shopping districts in Canada, Ottawa (with more public servants than any other Canadian city) and Kingston, all in Ontario, are so different from each other that you may not believe that you are in the same Country, let alone the same Province. Heading west, the major Cities worth visiting include Winnipeg, Regina (if you like Wheat, lots and lots of wheat), Calgary, Edmonton, Banff and Red Deer. In British Columbia, Victoria is a wonderful place to visit, no matter your age or likes and dislikes, with it's Victorian homes or lonely white-sand beaches. Vancouver is a major draw to the eco-tourists, as well as the many people who just want to see what the Olympic venues are going to be like.
So, what City, in all of these wonderfully beautiful, diverse and populous Cities is the most worth visiting? That answer would rely solely on what you, dear reader, want to get out of your experience. The fishermen and hunters would most likely head to the coastal cities, or to the Cities that are nearest the major lakes and rivers in Ontario and Quebec. The eco-tourist would head for British Columbia, probably staying in Vancouver and taking day-trips to the adrenaline-rushing adventures that are all too common ad so close by. Shoppers would head for Edmonton or Toronto. Baseball fans are stuck with Toronto, as they now host Canada's sole entry into Major League Baseball (the Blue Jays). Hockey fans have six Cities to choose from, but really should go to Ottawa to see a hockey game, because the crowds can be the loudest in the league at times, and in the arena, there really is not a single bad seat, you feel like you are a part of the game!
But for one single City in Canada to suggest that you should visit, I would have to select Bonavista, Newfoundland and Labrador. This is one of those Cities that when you get there, you ask yourself how quickly you could retire, and settle down in this place. Bonavista is the eastern-most City in North America, part of the Grosse Morne National Park system. And besides, Tickle cove is a short drive away, and who doesn't like to be tickled? You can sit on a cliff facing the Atlantic Ocean, and watch as icebergs slowly bob and weave their way along down the currents' draw, or watch the many different species of Whales that sing, dance, jump out of the water and spout water for all to enjoy. There are outfits that will take you out to an iceberg, and you then climb onto it, making a campfire and having lunch, as the marine life circles around the off-Worldly colours that the water changes into in the presence of the old, hard ice and it's ancient buried oxygen saturating the saltwater.
Seals, Puffins (a very colourful, very sweet little coastal bird that nests on the shorelines) and lots of codfish (and Mackerel, Lobster, clams, scallops, etc.), to Moose (one of the most populous Moose concentrations in North America is found here), Deer and fox, along with the good old Jack Rabbit and Foxes are the wildlife that you most definitely will see around Bonavista, Newfoundland, as long as you come in the spring to early summer time frame (before July 15). After that time frame, the sea becomes more about fish and whales than icebergs, and the little critters have come to their senses about wandering too close to civilization.
In the springtime, you do not have to go looking for wildlife, just have a seat, it will find you!