This one is a long day, especially if you spend any time exploring the geology of The Onion or searching for "ice caves" along the edge of the Wapta icefield. It fits the definition of a Class 1 scramble. The toughest bits are getting up and over the chokestone and then going up the rock ledges above Bow Hut, to The Onion. The views from the summit are well worth the effort.
Fall is a great time to undertake the long hike to Aylmer Pass in Banff National Park. Next time we'll do the Lake Minnewanka Trail portion on mountain bikes so that we have the time/energy to make the side trip to Aylmer Lookout.