What lay beneath the rough pasture of Slievereagh, in County Limerick, turned out to be considerably more layered than the surface suggested: a bivallate ringfort, meaning one enclosed by two banks and ditches, with a third fosse added on the eastern flank alone, apparently as a later reinforcement against the slope's natural drainage. It sits in the northern quadrant of a much larger archaeological complex on a hillside that scholars have long identified as the supposed site of Temaír Erann, the ancient cemetery of the Ernai tribe, a designation noted by the antiquarian T. J. Westropp in publications between 1917 and 1919.

The site was excavated in 1934 and 1935 by Seán P. Ó Ríordáin, who catalogued it as Ringfort No. 8 in what he called the Northern Group of forts on the hillside. The enclosure measures roughly 30 metres in diameter. Inside, excavation revealed two souterrains, the underground stone-lined passages commonly associated with early medieval ringforts, used for storage or refuge, as well as two house sites marked out by postholes and a stone hearth. The hearth, a flat surface of closely laid stones roughly 1.5 metres by 1.2 metres, showed no trace of charcoal across the surrounding area, leading Ó Ríordáin to conclude that occupation had been brief and never especially intensive. A wattle structure to the east of the southern souterrain added further complexity; its arc of stake-holes suggested not one but several successive buildings of that type had stood in the same area. Two additional ringforts sit close by, one immediately to the north and another roughly 30 metres to the south, and the whole cluster is set within the remains of a large field system.

The site sits in rough pasture on Slievereagh, and the eastern arc of the two banks with their intervening fosse remains the most legible feature on the ground, consistent with what Ó Ríordáin found before he put a spade in. Satellite imagery from between 2011 and 2013 confirms the curving earthworks are still traceable from above. Visitors approaching from the surrounding farmland should be aware that the broader archaeological complex is extensive and that neighbouring monuments are easily missed without prior reference to Ó Ríordáin's published plans or the relevant record entries. The relationship between the cluster of forts, the field system, and the old association with Temaír Erann gives the hillside a density of layered use that rewards careful attention to the landscape rather than any single feature.