As such an enormous country, there's always a reason to come back to Canada. Witnessing French-Canadian culture in Quebec, seeing the great cities of Toronto, Montreal, and Vancouver, and touring the great national parks of British Columbia are all superb options for your trip. In terms of the latter, Glacier National Park and Mount Robson Provincial Park are just two of the huge wildernesses that make Canada so beloved for its nature.
A more unique side of Canada lies in its North, where the country stretches beyond the Arctic Circle and you'll find the provinces of Nunavut, Northwest Territories, and Yukon. Yukon is famous for Dawson City, where the Gold Rush of the late 19th century took place, and the provincial capital of Whitehorse, which offers the opportunity to take Northern Lights tours.