The rail routes in the north and west of Scotland are the most scenic in the UK.  Even a Sprinter or a Shed looks good when photographed in a dramatic landscape, but I am going to mainly concentrate on 'real' trains!Not a landscape to begin with: 37039 is pictured in Oban station on 16 February 1985 at the head of the 1300 train to Glasgow.
37417 is seen near Attadale on 25 May 1988 with the 1010 from Inverness to Kyle of Lochalsh.
At Wick on 4 April 1984 47546 is reversing the stock of the 0640 from Inverness prior to running round. The Class 47 had taken over the train at Ardgay following the failure of 37017; according to the guard it had been removed from a freight service to Invergordon and it was then sent north light engine to rescue the passenger train.  I think that a Class 47 this far north was an extremely rare event.
Before the advent of the luxury day excursions currently being run as the "Northern Belle", Grampian Railtours of Aberdeen ran trips to Dufftown under this title. The train departed mid-morning from Aberdeen and stopped on the branch when a buffet lunch was served.  On arrival at Dufftown participants enjoyed a guided tour of the local distillery (with free dram of course!) before returning to Aberdeen in the late afternoon. 47644 is seen at Dufftown awaiting departure on 3 September 1986.
I appreciate that Perth is not really in the Highlands but this seemed the most appropriate place for this photograph. Long before Royal Scots Grey got the chance to stretch her legs on the main line she regularly appeared at open days. This one took place at Perth Yard on 13 April 1985.