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.

This col is unnamed on maps of the Ordnance Survey, but Alfred Wainwright termed it Sail Pass in his influential Pictorial Guide to the Lakeland Fells[1] Sail has a further connection to the south of the main ridge, a high level bridge to Ard Crags.

Ard Crags and its neighbour, Knott Rigg, form a lower parallel ridge to the south of the main range.

The southern flanks of the fell are drained by Sail Beck and its tributaries, flowing south west between the slopes of Wandope and Knott Rigg to Buttermere village.

Sail thus stands on the main watershed of the North Western Fells, a virtue not shared by the higher Grasmoor.

The Causey Pike Fault runs across the southern flanks of the fell, beyond which are the rocks of the Buttermere Formation.

[1] Perhaps most walkers will arrive at Sail as part of a ridge-top traverse, starting either with Grasmoor or Causey Pike.

From the former the track to High Coledale Farm is the initial objective, before crossing the Outerside ridge in the vicinity of Stile End.