It is the kind of feature that a farmer might work around for generations without knowing what it represents: a fulacht fia, the remains of a prehistoric cooking or processing site, built from the accumulated debris of repeated fire-cracking. The method involved heating stones in a fire until they were intensely hot, then dropping them into a water-filled trough to bring it to the boil. The shattered, blackened stones were discarded into a heap after each use, and it is precisely those heaps, dark with charcoal and fire-cracked fragments, that survive as the low mounds visible in fields across Ireland today.

What makes the Ballygrady site particularly interesting is that it does not stand alone. A second fulacht fia lies immediately to the west, and the proximity of both features to a stream is entirely characteristic; a reliable water source was essential to the whole process. A reference by Bowman in 1934 places a fulacht fiadh four yards north-east of a nearby earthwork described as a fort, and this mound may well be the same feature recorded then, suggesting it was already being noted, if not fully understood, in the early twentieth century. The pairing of two such monuments in close proximity hints at repeated or prolonged activity in the area, though whether the two mounds represent broadly contemporary use or entirely separate episodes is not something the surface evidence can settle.