Six small enclosures lie buried beneath a field in Walterstown, Co. Kildare, invisible to anyone walking the ground but legible from the air as a cluster of subrectangular cropmarks. Cropmarks form when buried ditches or walls affect how vegetation grows above them: the soil over a filled-in ditch retains more moisture, so the crop or grass above it stays greener or grows taller, tracing the outline of whatever lies beneath. In this case, the only record of these features comes from a single aerial photograph, on which six distinct enclosures appear side by side.

The site sits on a low ridge in level, well-drained pasture, a combination of topography and soil type that suits aerial detection well because the contrast between disturbed and undisturbed ground tends to show more clearly. The six enclosures share a broadly subrectangular form, suggesting some degree of planning or at least a common tradition of construction, though without excavation it is impossible to say who made them, or when. When the ground was visited, no earthworks were visible at all; heavy grass cover had obscured any trace of surface relief that might otherwise have hinted at what lay underneath.