The earliest written record dates to 1540, when documents mention a ‘castle or fortilage at Newbaa’ belonging to St Selskar’s Priory. By the time of the Down Survey in 1655-6, the site had evolved into what mapmakers depicted as a large house, though the Civil Survey conducted just a year earlier makes no mention of castles when recording that John Roche owned 198 acres here in St. Peter’s parish.

Today, visitors searching for traces of this possible fortification will find tantalising clues in an unlikely place; the stable yard of later buildings. The northwest wall of one structure, measuring about 1.2 metres thick, displays architectural features typical of medieval defensive construction, including a base batter on one side and a corbel on the other. These elements suggest this humble wall may be all that survives of the original castle structure.

The site occupies a strategic position on a low hill, overlooking what archaeologists have identified as a possible moated site to the northeast. This combination of elevated ground and potential water defences would have been typical of Anglo-Norman fortifications in medieval Ireland, when control of the fertile lands of Forth barony meant wealth and power. Though much of the castle’s story remains lost to time, these physical remnants and historical documents offer glimpses into centuries of ownership changes, from religious houses to private landowners, reflecting the broader patterns of Irish history from the medieval period through the Cromwellian conquest.