This fortification first appeared on the Down Survey maps of 1655-6 and continued to feature on Ordnance Survey editions throughout the centuries. The castle’s Irish name, ‘Caislean poll a-chaonnaigh’, translates poetically as ‘The castle of the hole of the moss’, hinting at the marshy landscape that once surrounded this defensive structure.

Historical records suggest the O’Dowds, a prominent Gaelic family in the region, erected this stronghold as a statement of their power and territorial control. When Ordnance Survey officials documented the site in 1837, portions of the castle still stood defiantly; a three-storey structure built, as they noted, ‘solely for strength’ rather than comfort or beauty. Local memory preserved numerous legends and place names connected to the castle, though these stories have sadly faded alongside the physical remains.

Today, visitors to Cabraghkeel will find only traces of what once was: a circular, flat-topped mound measuring 14 metres across and standing 1.4 metres high. Modern development has taken its toll; a roadway now covers much of the western and northern sections, whilst a drainage ditch cuts through the southern side. Two quarry holes pierce the mound where stone was likely robbed for other constructions, and no masonry remains visible. What survives is a subtle reminder in the landscape of the medieval powers that once controlled this strategic position overlooking Killala Bay, where river meets sea on Sligo’s Atlantic coast.