Sitting on a low, round-topped rise in gently undulating pasture, the site had been levelled long before anyone thought to record it formally. What survives is not stone or earthwork but a ghostly ring of light green grass, a narrow band roughly 1.2 metres wide, standing out in vivid contrast to the surrounding vegetation. That strip of different-coloured growth almost certainly marks a backfilled fosse, the outer ditch that would once have defined the enclosure. A ringfort, to give the term some context, is a circular enclosed settlement of early medieval date, typically bounded by one or more earthen banks and ditches, and once a common feature across the Irish countryside. This one measured approximately 25 metres north to south and just over 20 metres east to west, with a slight interior rise toward the centre. On the western side, a 3.4-metre break in the grass band has been read as the likely position of the original entrance gap.

The site had been noted, if not in detail, well before the 1971 survey. The 1837 Ordnance Survey Fair Plan map annotated the spot simply as 'Fort', suggesting local awareness of something significant in the ground even then. It sits around 350 metres south-west of where Killininneen House now stands, itself built on the site of an earlier Killininneen Castle. That layering of occupation, a medieval castle replaced by a Georgian or later country house, with an older ringfort quietly subsiding in the pasture nearby, is not unusual in the Irish midlands, though it rarely announces itself so discreetly. By the time aerial photography had advanced enough to examine the site digitally, no surface trace remained visible at all. The 1971 description, with its careful measurements and its account of that telling stripe of grass, now reads as the last clear record of something that has since become fully invisible.