What makes this site quietly remarkable is precisely its absence: a structure that once registered clearly enough on the landscape to be recorded on the Ordnance Survey's six-inch map of 1842 has since been levelled entirely, leaving no visible surface trace in the pasture that now covers it.

The 1842 map shows the enclosure as an irregular oval platform, measuring roughly forty metres on its north-east to south-west axis and around thirty metres across. Enclosures of this kind are among the most common archaeological monument types in Ireland, typically consisting of a raised or ditched area defined by an earthen bank, and associated in many cases with early medieval settlement or farming activity. They vary considerably in size and form, and without excavation it is rarely possible to say with certainty what purpose any individual example served. At Knockboghil, the platform's irregular oval shape was noted before the land was brought under more intensive agricultural use, which is almost certainly what erased whatever earthwork remained.