Lake Minnewanka is a stunning place to visit if you are in Banff National Park. In the summer months there is a moderate out and back hike along the lake that is roughly 15km that allows you to see the beautiful views of the surrounding area. You can also take a boat tour of the lake to learn the history of the lake and town, as well as bring your own paddle board, canoe or kayak and tour around on your own. During the winter you can almost always find people skating around playing hockey on this beautiful huge lake.
Something a lot of people who are visiting the area are not aware of is the underwater ghost town in the lake! If you want to check it out you can scuba down and take a tour that not all are lucky enough to experience, so if you have the gear and the time; taking a deep dive into this glacier lake should definitely be on your list of things to do.