It is a univallate hillfort, meaning it is enclosed by a single bank and external ditch rather than multiple lines of defence, and from the outside it reads as modest, even unremarkable. What makes the site genuinely strange is the layering of time compressed within its 1.5 hectares. Beneath the hillfort's construction material lie the traces of a much older cairn, a burial monument perhaps 23 metres in diameter, associated with thirteen cremations, three inhumations, and at least five food vessels. The cairn was not incorporated respectfully into the later fort; it was levelled, probably by the Iron Age people who reoccupied the site.

Excavations carried out by Gerhard Bersu between 1948 and 1949, and published by Raftery in 1969, initially suggested a fourth-century AD date for the hillfort, largely on the strength of Roman material recovered from the site, including bronze bracelets of Romano-British type, two Roman toilet implements, and a copper coin datable to AD 337 to 340, during the reign of Constantine the Great. That dating was later revised considerably. Coarse-ware pottery found underneath the bank, within the ditch fill, and in occupation layers inside the fort pointed to an origin in the Late Bronze Age, and a radiocarbon date obtained from charcoal in an occupation layer returned a range of 810 to 550 BC. Ó Floinn, reanalysing the artefact assemblage in the late 1990s, supported this earlier date, noting that three blue glass beads from the habitation layers were consistent with Late Bronze Age manufacture, and that a fourth bead closely paralleled examples from the continent and from Rathgall hillfort in Co. Wicklow. The picture that emerges is of a site first used for burial in the Bronze Age, then enclosed and occupied during the Late Bronze Age or Early Iron Age, and revisited again in the Roman period, with the Roman artefacts likely reflecting contact or exchange rather than direct Roman presence. The hillfort occupies a strategically legible position, overlooking Kilkenny town and a north-south routeway running through the gap between the Slieveardagh Hills and the Castlecomer Hills, and it is not difficult to see why successive communities found the summit worth returning to.