The example at Moylisha in County Wicklow breaks that convention in a quietly notable way. Its main chamber, rather than tapering, actually widens towards the south-east end, a configuration the records flag as uncharacteristic. It is a small deviation, but in a monument type defined by consistency across hundreds of sites, it is the kind of detail that makes an archaeologist look twice.

The tomb sits within a subrectangular cairn measuring roughly 13 metres by 10 metres, enclosing a gallery 7.5 metres long aligned on a north-west to south-east axis. At the north-west end, a small antechamber, barely 0.8 metres by 0.5 metres, is separated from the main chamber by a low sill stone. Inner walling follows the contour of the gallery sides and curves around the south-east end, and a single roofstone, now displaced, still lies inside. The tomb was excavated in 1937, and what came out of the base of the cairn gives a layered sense of the site's long life. Bone fragments and sherds of coarse pottery are the expected markers of prehistoric burial and use. Two stone discs are harder to interpret. More surprising still were two halves of a sandstone mould for casting a bronze looped spearhead, found on the east side of the cairn base. Spear-casting moulds are Bronze Age objects, and their presence here, almost certainly the result of later disturbance of the cairn, suggests the site remained a place of human activity long after the original builders had gone. The cairn itself once stood 1.5 metres high, but stone was robbed from it to construct the low protective wall that now encloses the monument, meaning the tomb effectively contributed to its own preservation.