On the Ordnance Survey six-inch sheet of 1842, a clearly defined circular enclosure roughly 25 metres across was recorded, with a small secondary feature, about 5 metres in diameter, marked at its centre. By the time the same area was surveyed again in 1905 and 1935, the picture had shifted: the enclosure appeared penannular, meaning nearly but not quite a full ring, open to the north-east, and somewhat larger at around 30 metres across. Whether that change reflected actual deterioration, a difference in the surveyor's eye, or both, is not recorded.

The site itself is a rath, the Irish term for a ringfort, a form of enclosed farmstead that was in widespread use during the early medieval period, roughly between the fifth and twelfth centuries. Thousands survive across Ireland in varying states of preservation, but Ballinaltig Beg's example belongs to the quietly vanishing category. It has been levelled, most likely by agricultural activity over generations, and what remains today is little more than a slight rise in the ground, circular in plan and measuring approximately 36 metres east to west and 34 metres north to south. The original interior feature that appeared on the 1842 map, possibly a souterrain cap or the outline of a structure, is no longer distinguishable in any recorded form. The enclosure that once defined a household boundary now announces itself only as a gentle swelling in the grass, easy to miss and easier still to walk across without recognition.