Construction of the site took place between 2900 and 2600 BC, though there were possibly earlier buildings before 3000 BC. A tomb was later built into the site. Debris from the destruction of the tomb suggests the site was out of use between 2000 BC and 1700 BC. The 13 primary stones form a circle about 13 m in diameter, with a long approach avenue of stones to the north, and shorter stone rows to the east, south, and west. The overall layout of the monument recalls a distorted Celtic cross. The individual stones vary from around 1 m to 5 m in height, with an average of 4 m, and are of the local Lewisian gneiss.