People seems to rarely get to the highest point of Castle Mountain, such is located northwest, close to Stuart Knob. This is an easy scramble but fitness wise it is more challenging with about 27 km overall.
You first get to Rockbound Lake and then keep walking along the lake on its right where you'll see a flag and a cairn. From there, it’s straight up to the right of a first gully that you will traverse left easily when arriving at a rock band.
Then, you'll see the trail when taking some more elevation. You go straight to the end of the "plateau" walking in this gigantic amphitheatre and scrambling up easy rock bands before attacking the scree slope sideways going to your left to get closer to Castle-Stuart col. Once at the "false summit", you just keep going for about 200 metres, you will see the summit cairn from there. Return the same way. I suggest that you try out Stuart Knob first on your way up and then summit Castle Northwest. They are pretty close from each other.
Elevation of Castle Mountain True Summit Northwest of 2811 m (2850-2882 m on the Web)
GPS TRACK: This my GPX track from a three summit hike. You don't want to hike up the second gully on Helena Ridge and rather keep going to Castle-Stuart col by walking through the amphitheatre.
From Banff, drive north up to 93 South/Castle Junction. Take this exit and keep going down to Castle Mountain. Turn right at the stop sign and the parking lot will be on your left a few seconds later, Rockbound Lake parking lot.
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