Built into its base is a low, grassed-over stony bank, the last legible trace of an early medieval cashel, a type of ringfort defined by its stone construction rather than the earthen ramparts more commonly associated with such enclosures. The cashel's circular boundary, once perhaps a metre or more of dry-stone walling, has been quietly cannibalised by the landscape around it, its stones reused, its purpose forgotten, its shape absorbed into the working geometry of a field.

The first edition of the Ordnance Survey six-inch map, produced in Ireland during the 1830s, recorded the site as a circular enclosure with a diameter of approximately fifty metres. That cartographic snapshot is now among the most informative things we have. Ringforts of this kind, known in Irish as caiseal when stone-built, were typically the enclosed farmsteads of early medieval Ireland, occupied roughly between the fifth and twelfth centuries. Thousands survive across the country in varying states of preservation; many, like this one, survive mainly as anomalies in the field pattern, their outlines detectable only because later generations found it easier to build along an existing curve than to clear it entirely. The stony bank at Luggawannia is thought to preserve the line of the original enclosure from the west, running through north to north-north-east.