Aerial photographs taken in July 1989 as part of a systematic survey captured a regular grid of rectilinear cropmarks spread across roughly six hectares. Cropmarks form when buried features such as ditches, walls, or banks affect the growth of crops above them, producing subtle variations in colour and height that only become visible from altitude, particularly during dry spells when the soil stress is greatest. What emerged at Killuragh was a relict field system, a ghost of organised agriculture pressed into the earth, with the largest single identifiable field measuring approximately one hundred metres by one hundred metres.

The perpendicular alignment of many of the boundaries suggests deliberate, planned land division rather than organic accumulation over time. Systems like this can date anywhere from the Bronze Age through the early medieval period, and without excavation it is difficult to assign Killuragh a more precise date. What the aerial evidence does confirm is that a community once divided this ground with some care, laying out fields of considerable regularity across an area that today gives little outward sign of what lies beneath it.