59.0015°N, 3.2296°W.
The Ring of Brodgar stands on a narrow isthmus between the Lochs of Stenness and Harray on the Mainland of Orkney, Scotland, the third largest stone circle in the British Isles. It is conventionally dated to between 2500 and 2000 BCE in the late Neolithic, and originally consisted of about 60 stones of local Orcadian flagstone set in a true circle 104 metres in diameter and surrounded by a rock-cut ditch up to 3 metres deep and 9 metres wide; 36 stones remain standing or fallen, several struck by lightning. The ring sits at the centre of the Heart of Neolithic Orkney World Heritage Site, in line with the older Stones of Stenness, the Ness of Brodgar excavation, and the Maeshowe chambered cairn.
The ditch was hewn from solid bedrock with antler picks, in a place where the nearest tree large enough for a handle was already a memory.