The Rudston Monolith late Neolithic standing stone
Interestingly there are four cursi (or cursuses) nearby, three of which converge on the monolith. Cursi are Neolithic parallel ditches or dykes which can often run for miles (the Dorset cursus is one such example) and resemble race tracks or some sort of ceremonial pathways.
Apparently the small stone once stood much closer to the Monolith and may have been part of a stone circle.