a friend and I hiked up Heart mountain (just before canmore) and did a ridge walk along the top before comming down on the other side of the valley. Amazing views from the top. I'm a begginer when it comes to hiking so my legs were killing me when I was Hiking up the mountain. I had to take a nice long break at the top and quite a few inbetween. Can't go back down the same way you go up because it gets steep at some points, so you pretty much have to do the ridge walk and go back down on a gentler sloping side of another mountain. It took me and my friend about 6 hours because I kept slowing him down. It's not easy but I think it's rated at moderate. Here's a picture of part of the ridgewalk we did once we were at the top.
I also like hiking up Dura creek near exshaw which was pretty easy, but you need decent hikers because there's a lot of lose rocks. Relatively flat though. Depending on how long you want to hike for, you can go up as far as you want because you come back the same way.
These aren't quite in Banff. They're closer to Canmore.
