In 1935 Yealand archaeologist Colonel Oliver North carried out a survey of the site. He plotted the position of 6 limestone boulders and demonstrated that 4 of them were on the circumference of a circle 460 feet in diameter. He also noted depressions in the ground which might have housed other stones from the circle. Two remaining stones could conceivably have formed part of an outer ring, and were both about 330 feet from the centre of the supposed monument. Colonel North detected what he thought might be a large ditch on the north-western side of the circle. And he speculated that some of the large stones used as foundations for the Rawlinson summerhouse might have been pillaged from the stone circle. Others have suggested that summerhouse was itself built upon a cairn.
There has never been an archaeological dig on the site and some experts are not convinced that the stones are anything other than lime-stone boulders randomly deposited by a retreating glacier. But Summerhouse Hill is an atmospheric place.
Leighton Moss Ice Age To Present Day by Andy Denwood (Published 2014)