Interpretation
They are probably Neolithic ritual or ceremonial monuments similar to a henge but this interpretation is somewhat speculative due to the presence of external rather than internal ditches, a feature which makes them unique in Britain. Although no dating evidence has been found, they appear to be contemporary with Stonehenge, i.e. Neolithic circa 2500 BC - 2180 BC. Two round barrow cemeteries, Ashen Hill and Priddy Nine-Barrows, located less than 1 km (0.62 miles) south of the Circles, would seem to imply that the area to the northeast of Priddy held ritual significance into the Bronze Age.
Read more about this topic: Priddy Circles