Today, only the first arch of this medieval stronghold survives, a fragment of what was once a substantial fortification. When surveyed in 1840, the castle’s remaining structure measured approximately 6.6 metres by 4.2 metres, with impressively thick walls of 1.6 metres, though the external faces had already crumbled away. The castle stands east of the old Kilcullane Church, and both structures appear side by side on the Down Survey map drawn between 1654 and 1657, offering a glimpse of how these twin monuments once dominated the local landscape.

The castle’s history reads like a medieval property ledger, with ownership passing through various Anglo-Norman and Irish families over the centuries. In 1244, Adam de Anno held Kilcullane for the rather specific rent of a soar hawk and half a mark of silver, with the property later passing to Godfrey de Anno. By 1287, the manor had changed hands to J. Daundon, who held it from Sir T. de Clare for the curious annual payment of one pair of furred gloves and sixpence. The Browne family appear to have taken control sometime after Ralph Brun’s tenure, maintaining their grip on the castle through the Tudor period; Thomas Browne held it in 1583, with Walter and E. Browne receiving a grant for the property in 1607.

By the mid-17th century, however, Kilcullane Castle had fallen into decay. The Civil Survey of 1654-56 paints a picture of decline, recording that Teige O’Grady’s lands contained a ‘decayed Castle & 14 Cabins’, suggesting the once-proud fortress had been reduced to ruins whilst a small settlement had grown up around it. Edmund Baggott and D. O’Grady had been granted the lands in 1610, and by 1655, the castle remained in O’Grady hands, though described simply as ‘decayed’. This gradual deterioration from medieval stronghold to romantic ruin mirrors the fate of countless Irish castles, leaving us with tantalising fragments of a turbulent past.