In July 1989, an aerial survey caught the site at just the right moment, when differential crop growth caused by buried features below the soil revealed two concentric fosses, the ring-shaped ditches that once defined the boundary of the enclosure. Cropmarks of this kind appear when buried ditches or walls affect how overlying vegetation grows, typically showing as darker or lighter strips in a ripening cereal field. The photograph that captured this site also recorded a macula, a dark stain or patch, in the southern half of the enclosure interior, a feature that might indicate the presence of decomposed organic material, a filled pit, or some other buried deposit.

Two parallel linear cropmarks were also visible approaching the enclosure from the south, suggesting an entrance route or a sunken trackway leading towards it. Further linear cropmarks to the south and west of the site are thought to represent levelled field boundaries, the ghost traces of an agricultural landscape that has been ploughed and reshaped over centuries until almost nothing remains above the surface. The enclosure itself, with its double-ditch arrangement, fits a pattern well known in Irish archaeology: enclosed settlements of the early medieval period, sometimes called ringforts, were commonly defined by one or more circular earthen banks and ditches. A site with two concentric fosses would have been a reasonably substantial one, though without excavation it is impossible to say with certainty what period the Bridgetown enclosure belongs to or what activities took place within it.