But from the air, under the right conditions, the soil gives something away. When crops grow unevenly over buried ditches and disturbed earth, they betray the outlines of structures long since levelled, producing what archaeologists call cropmarks. It was through aerial photography, carried out in August 1995 and again in August 1996, that a ring-ditch came into focus here, a circular ditch roughly 15 metres in diameter, its presence invisible at ground level but legible from above as a faint ghostly ring pressed into the growing crop.

What makes Garryduff particularly significant is that this ring-ditch is not alone. Four others have been identified in the same area, ranging from about 12 to 15 metres in diameter, clustered within a relatively compact zone. Ring-ditches are generally understood to be the surviving traces of prehistoric burial mounds, the encircling ditch that once defined a barrow, even after the mound itself has been removed by centuries of cultivation. About 30 metres to the south lies the ploughed-out remnant of an actual barrow, now reduced to a soil mark, its physical presence erased by tillage but still detectable. Taken together, the five ring-ditches and the levelled barrow form what appears to be a prehistoric funerary landscape, a cemetery whose monuments were once visible on the surface but have been slowly worn away over millennia of agricultural use. The grouping is consistent with Bronze Age burial practice in Ireland, where the dead were sometimes interred beneath earthen mounds arranged in loose clusters across the landscape.