The Achnashellach forest contains one of the most dramatic imbricate thrust stacks of the Moine Thrust Belt. It is made of Cambrian quartzites and Torridonian sandstones. Thrust ramps and associated folds are picked out by the colour contrast between these two rock types and by the regular bedding in the quartzites. The area is without equal in NW Scotland for the demonstration of large-scale imbrication.

The view onto Beinn Laith Mhor is available - on a good day - from the summit of Sgorr Ruadh.