The ground holds the remnants of what was probably a rath, a type of circular earthen enclosure used in early medieval Ireland as a farmstead or settlement, and the site is named Lismeel, the "lios" element of that name being the Irish word for just such a fortified enclosure. What survives today is a kidney-shaped platform, roughly thirty metres along its longer axis, edged by a broadly slumped scarp that rises to nearly two metres at its highest point and blends so gradually into the natural contours of the hill that the boundary between human construction and landscape is genuinely difficult to read. A very shallow depression curving around the northern arc may be the ghost of a fosse, the surrounding ditch that would originally have defined the enclosure.

The 1838 Ordnance Survey six-inch map records Lismeel as a clearly circular enclosure, forty to forty-five metres in diameter, and names it explicitly. By later map editions, the cartographers were already depicting it as an irregular, hachured feature, suggesting that the process of degradation was well under way during the nineteenth century. The site sits within the former grounds of Ballinamore House, an 18th-century country house, and that proximity may partly explain what happened to it. The southern and south-western sections have been levelled and partly quarried out, the kind of opportunistic stone-robbing and land-clearance that was common when historic earthworks stood inconveniently close to working estates. The hollow of wettish ground to the south-east is unrelated to the rath itself, a small reminder that the natural and the archaeological can sit side by side in a field without either announcing itself clearly.