 The northern edge of the fell is marked by a steep range of crags which drop sharply to the floor of Eskdale.These crags are cut by the cascades of Stanley Force and Birker Force, two of the most spectacular waterfalls in the Lake District.Geologically, Birker Fell is of importance as the type locality of the Birker Fell Formation (BFF) of the Borrowdale Volcanic Group (BVG).