Ben Challum is probably the most famous of the Mamlorn Hills due to its easy access from the A82 in the west and also due to its fine summit ridges. Ben Challumís southern slopes are well seen just north of Crianlarich although the true summit is actually hidden.
The summit is the intersection point of 3 ridges. The eastern ridge drops down to Glen Lochay. A south east running ridge starts in Strath Fillin; this is the most common approach but not necessarily the most exciting. The ridge runs over the subsidiary top of Ben Challum. The north east ridge runs to Bealach Ghlas-Leathaid and is not normally used as a route of ascent, but that is not to say it canít.
A much more exciting ascent route is from the east in Glen Lochay via the eastern ridge as mentioned previously. This ridge offers some great scrambling opportunities with craggy outcrops.