Harpsdale Fishery is a relatively simple place to find.  As you can't be much further north than the Fishery I have only included directions from the South.  Drive North on the A9 towards Thurso.  Approximately 10 miles from Thurso turn left towards Westerdale along the B870.  Approx 1 mile after this turning you will see a sign post pointing to your right for Halkirk.  Take this right turn and drive for approx 3.5 miles until you see the sign for Harpsdale Fishery Park on your right hand side.  If you reach Halkirk and go over the railway crossing you have gone too far.