Though no stones remain visible today, this rectangular plot measuring roughly 15 metres northwest to southeast and 5 metres in the opposite direction was clearly significant enough to warrant marking on Ordnance Survey maps from 1835 and 1876, where it appeared in distinctive italic lettering as the ‘Site of Old Castle’.

The mystery deepens when examining earlier records. The Down Survey maps from 1656 to 1658, created in the aftermath of the Cromwellian conquest of Ireland, show no castle at nearby Knockafea. This absence raises intriguing questions: was the structure already gone by the mid-17th century, or did it disappear in the turbulent years that followed? Local historian Davies noted in 1947 that no traces remained at ground level, suggesting that whatever stood here had long since been reclaimed by the landscape.

Today, visitors to this quiet drumlin slope will find little to mark the spot where this castle allegedly stood. Yet its persistent notation on 19th-century maps hints at a structure that lingered in local memory long after its physical presence vanished. Whether it was a modest tower house, a fortified dwelling, or perhaps something misidentified by later cartographers, the Old Castle of Knocknaveagh remains one of Cavan’s more elusive historical puzzles, its true nature lost to time and the Irish weather.