The only way it came to light was from the air, when a aerial survey in July 1989 captured a cropmark, the faint differential in how plants grow above buried soil disturbances, tracing the curve of a fosse, or enclosure ditch, roughly fifty metres across. The circle is approximate but unmistakable, and it is the kind of shape that recurs throughout the Irish countryside wherever early settlements were dug into the earth and then slowly swallowed by subsequent farming.

Enclosures of this type are generally associated with the early medieval period in Ireland, when ringforts, known variously as raths or cahers depending on whether their banks were of earth or stone, served as defended farmsteads for individual families or small communities. The fosse here is the negative space left by such a boundary, the trench that would originally have sat inside or alongside a raised bank. What the 1989 photograph also caught was a linear cropmark running east to west across the northern third of the site, extending out into the surrounding field. This is thought to represent a levelled field fence, a later agricultural boundary that cuts across the earlier enclosure without any apparent awareness of, or concern for, what lay beneath it. The two features together suggest a landscape that has been continuously worked and reorganised across many centuries, each era quietly overwriting the last.