There is nothing to see now, no earthwork, no raised ground, no shadow of a bank, but the place was real enough to be carefully recorded by the Ordnance Survey in 1842, when their six-inch mapping team noted a hachured circular enclosure roughly twenty-five metres across.

That map notation is now the primary evidence that anything was ever here. The enclosure was a rath, the Irish term for a ringfort, the most common monument type in the Irish countryside. Ringforts were typically enclosed farmsteads of the early medieval period, roughly the fifth to twelfth centuries, defined by one or more earthen banks and ditches surrounding a domestic space. Thousands survive across Ireland in varying states of preservation; thousands more do not. The Knockagolig example falls into the latter category. At some point between its recording in 1842 and the present day, it was levelled, most likely through agricultural activity, until no surface trace remained. The pasture now shows nothing of what the surveyors once thought worth marking.