View from southeast, with the Comet Stone in the foreground. Ring of Brodgar, c. 2500 BC. Mainland, Orkney Islands, Scotland. Measuring nearly 104 m in diameter, this impressive Neolithic monument is a true circle that is thought to have originally consisted of 60 stones. Today 27 stones remain standing, ranging in height from 2.1 m to 4.7 m. The ring is positioned on a scenic strip of land between the freshwater Loch of Harray (to NE) and the saltwater Loch of Stenness (to SW).