sentences:  It is quite a large fell and forms the eastern wall of the Duddon Valley for several kilometres, in fact all drainage from Grey Friar goes to the Duddon Valley and not to Coniston Water.The Coniston (or Furness) Fells form the watershed between Coniston Water and the Duddon valley to the west.The range begins at Wrynose Pass and runs south for around 10 miles before petering out at Broughton in Furness on the Duddon Estuary.