Visited 30.03.26
If you are driving near Helston it is a no brainer to take this 3.5 mile detour through Cornish lanes to Prospidnick Longstone on the roadside. The ancient stone slab reaches an impressive 9 feet high. There is a convenient gateway c. 20 yards NE of the stone allowing a closer inspection. My google maps route from the A394 at Helston can be viewed on Prospidnick Longstone.