The structure is a ring-ditch, the buried remnant of a circular enclosure whose fosse, or ditch, survives only as a cropmark, a phenomenon that occurs when buried features cause the soil above them to retain or shed moisture differently, producing variations in the colour and height of growing crops that become readable in aerial photography. The enclosure is small, roughly fifteen metres in diameter, and what we know of its shape comes from a single aerial photograph taken in July 1989 as part of a systematic aerial survey of Cork.

Ring-ditches of this kind are found across Ireland and tend to attract cautious interpretation. Some are the ploughed-down remains of Bronze Age burial mounds, the central mound long since eroded away, leaving only the surrounding ditch as a ghostly signature in the soil. Others may be the foundations of small enclosures associated with settlement or ritual. Without excavation, the Bridgetown example cannot be assigned confidently to any one category. What the aerial photograph also revealed were several linear cropmarks running across the same fields, to the east and west of the enclosure, which are thought to represent a relict field system, a landscape of boundaries and divisions that was in use at some point in the past but was never completed, or at least no complete field boundary has been traced from the available evidence. The enclosure and these field lines together suggest a stretch of countryside that was once organised and worked, its geometry now only recoverable through the accident of dry summers and the right angle of light.