Twenty-five of the holes were excavated by Hawley in 1920 and seven more in 1924. In 1950 Stuart Piggott and Richard Atkinson dug two more Aubrey Holes which brought the total excavated to thirty-five, including one that Richard Colt Hoare may have encountered whilst digging beneath the fallen Slaughter Stone (so named from its reddish coloration) in the early nineteenth century. It was found that the pits were an average of 0.76m deep and 1.06m in diameter. Twenty-five of the pits contained later cremation burials inserted into their upper fills along with long bone pins which may have secured leather or cloth bags used to hold the remains. Their presence makes Stonehenge Britain's oldest cremation cemetery.