This is the Neolithic Croft Moraig standing stones which lie a few miles east from the lovely village of Kenmore on Loch Tay.
They are believed to be around 2000 years old and in 1819 a man called Alexander Huchenson drew up the first decent ground plan of the stones and later they were properly excavated in 1965. The stones are often overlooked by travellers passing by so if you are in the area then go and have a look .