A cropmark roughly 85 metres in diameter, the feature shows up in aerial imagery as a ghostly ring, the kind of anomaly that ground-level walkers would pass through without any sense that the earth beneath their feet was shaped by deliberate human effort.

Cropmarks appear when buried features, whether ditches, walls, or banks, affect the growth of vegetation above them. Filled-in ditches, for example, tend to retain moisture better than the surrounding soil, producing lusher, taller crops that photograph as darker lines from above. Conversely, buried stonework or compacted surfaces can stress vegetation into paler, thinner growth. At Liscolman, the circular outline picked up in a photograph taken in July 2018 points to something substantial underneath, most likely a large enclosure of the kind associated in Ireland with significant early medieval settlements, ceremonial sites, or high-status farmsteads. At 85 metres across, it falls well beyond the dimensions of a typical ringfort, which rarely exceeds 60 metres in diameter, suggesting either a site of considerable importance or a more complex function. The discovery was brought to light by Simon Dowling and recorded in 2019.

Because the site is known only as a cropmark, there is nothing visible at ground level, and no excavation has been recorded here. What the landscape around Liscolman conceals in its soil remains, for now, a matter of aerial geometry rather than excavated evidence.