FA- Dominion Survey via West Slopes
Mt.Hardisty is easily seen as a long low-rising orange rocky peak just north of Mt.Kerkeslin, or about 6km north of Athabasca Falls. It is a very easy scramble, but can be a bit knee-jarring over the terrain up the slope in spots.
Park as for Horseshoe Lake and follow it around the north side, or park along the road north of the parking area, drop down to the lake and follow it around the northern side then find the easiest looking way through the lower reaches of the peak in order to gain the upper slope. Hike up this long slightly angled route to the summit Return the same way.
There may be a better trail as this is going on two ascents done nearly 25 years ago and the Info Center in Jasper may have more detailed info.
If you have time after, and the day is warm, think swim trunks and a beach towel for a swim in the Caribbean blue Horseshoe Lake. There are many small cliffs that rise higher and higher, 80 feet high being the tallest section. There are endless “deep water soloing” options along this lake and it has been a cliff-jumpers paradise since the 1920s, so claiming any “route” as a deep water solo FA may be asinine.
Apparently a route up the North Ridge was done in 1971 as per the ole Green Bible (Rockies North by Putnam). I recall Dave Marra telling me in about 1993 that he and a friend climbed the north side of Hardisty but nothing further remembered if it was the 1971 route or a new route, will have to ask him ….