The circle is 104 m in diameter, and one of the largest to be found in Britain. The henge was comprised of 60 stones, of which 27 remained standing at the end of the 20th Century. The stones are set within a circular ditch up to 3 meters deep and 9 meters wide that was carved out of the solid bedrock by the ancient residents.
The surrounding area is full of other standing stones and round piles of earth atop prehistoric tombs, making a significant ritual landscape. Although its exact purpose is not known, the proximity of the Stones of Stenness and its Maes Howe tomb make the Ring of Brodgar a site of major importance.