Perched on Corrandhu Hill, about three kilometres east of Ballyragget village in County Kilkenny, lies one of Ireland's most impressive prehistoric hillforts. Dating back to the Late Bronze Age, this ancient fortification sprawls across the western foothills of the Castlecomer plateau, occupying a narrow ridge that rises to just over 250 metres above sea level. The site commands sweeping views across the surrounding countryside, though today much of the western slopes have been overtaken by dense forestry plantations that obscure some of the fort's original features.

The hillfort consists of two massive concentric enclosures that encircle the summit, creating a formidable defensive structure covering nearly nine hectares. The outer rampart forms an impressive sub-circular circuit measuring over 330 metres north to south and 351 metres east to west, whilst approximately 100 metres inside sits a smaller oval enclosure. Though centuries of weathering have reduced these once mighty ramparts to low mounds of scattered stones and earth, careful archaeological investigation has revealed their original construction: stone banks with external ditches, reinforced by small wooden palisades on the inner sides. The inner ditch was rock-cut, measuring about 1.4 metres deep and 2.5 metres wide, whilst the outer ditch reached 1.2 metres in depth.

Recent excavations and geophysical surveys have brought fascinating details to light about life within these ancient walls. Radiocarbon dating confirms the Late Bronze Age origins of the site, whilst geophysics has identified three possible original entrances and evidence of internal structures, including pits and what may have been a hut. Rather grimly, according to nineteenth-century accounts, human bones were discovered during quarrying operations both on the plateau's fringe and within the ramparts themselves, adding another layer of mystery to this atmospheric hilltop fortress that once watched over the ancient landscape of Kilkenny.