The North Western Fells occupy the area between the rivers Derwent and Cocker, a broadly oval swathe of hilly country, elongated on a north-south axis. Two roads cross from east to west, dividing the fells into three convenient groups. The central sector, rising between Whinlatter Pass and Newlands Pass, includes Sail. The highest ground in the North Western Fells is an east-west ridge in this central sector, beginning with Grasmoor above Crummock Water and then gradually descending eastwards over Crag Hill, Sail, Scar Crags and Causey Pike.