 After St Fillans the route was undulating, but with equally severe ruling gradients, and the final section from Lochearnhead to Balquhidder also had a section of continuous 1 in 60 rising.The line opened from Comrie to St Fillans on 1 October 1901, and from St Fillans to Lochearnhead on 1 July 1904; finally from Lochearnhead to Balquhidder on 1 May 1905.The line closed on 1 October 1951 except for the subsequent intermittent use for the Glen Lednock catchment scheme.