The northern slopes of Illgill Head form the spectacular Wastwater screes, which sweep down from the summit into the lake and make this one of the most photographed hills in the Lake District. The summit itself is flat and grassy, and the best views are downwards.
A good approach is to climb beside the deep gorge of Greathall Gill and onto Whin Rigg, the western outlier, which actually has better views of the lake far below. From there, keep as close to the edge as possible on the traverse to the higher top. On a clear day, the view from Wasdale Head takes in the highest hills in the Lake District.