Locals have long called the surrounding area the moat field, which is one of those quietly telling pieces of folk memory that tends to outlast the monument itself. The feature is a ditch barrow, a prehistoric funerary or ritual mound type defined by an encircling ditch or fosse rather than a simple heap of earth, and this one has been worn down considerably by time, waterlogging, and the steady passage of agricultural activity.

The Archaeological Survey of Ireland recorded the site in 2008, describing a roughly circular area measuring approximately 20 metres north to south and 18 metres east to west. What survives above ground is mainly a scarp, a low earthen edge or bank, roughly 3.4 metres wide and standing to about 0.65 metres in height. Traces of a shallow external fosse, the ditch that would originally have defined the outer boundary of the monument, remain faintly visible when viewed from the north-west, north, and north-east. The interior retains a gentle south-facing slope. The survey was compiled by Alison McQueen and Vera Rahilly, whose notes were uploaded in July 2020. A related monument, a ring-barrow, lies approximately 170 metres to the north-east, suggesting this corner of Ballynagally once held some significance in the local prehistoric landscape, though the two monuments have not been formally linked by excavation.

The earthwork is set in poorly drained pasture, so the ground underfoot is likely to be soft and uneven, particularly in the wetter months. The outline of the earthwork, easier to read from above than at ground level, is visible on satellite imagery taken in both June and November 2018, which gives some sense of how subtle the physical remains have become. Anyone approaching on foot should look for the low curving scarp rather than any prominent mound; at 65 centimetres high it sits well below eye level and is easy to walk past without registering what it is. The presence of the nearby stream to the south-east and the companion ring-barrow to the north-east makes the broader field pattern worth taking in slowly.