For fans of #standingstonesunday, I have a conundrum. Pictured is a stone that is undeniably standing but I don't think it was erected by human hands, or was it? Your thoughts appreciated. It is located approximately 250m SSW of the campsite at #Achmelvich #Sutherland #Scotland . Note that this stone is not recorded as a standing stone as far as I can determine (eg trove.scot). All the same it's very very upright!