Though nothing remains visible today, historic maps from the early 18th century mark its location; Bateman’s map of 1716-1717 shows a castle symbol at this spot, roughly 200 metres west of the county boundary. According to local knowledge, the castle site lies in a field east of what is now Springdale House.

The castle’s history is tied to one of medieval Ireland’s most prominent families. Charles Smith, writing in 1750, recorded that Kilmacow Castle was built by John FitzGerald, the youngest son of Thomas, the 8th Earl of Desmond who was executed at Drogheda in 1467. The FitzGeralds were among the most powerful Norman families in Munster, and this castle would have been one of many strongholds helping them maintain control over their vast territories.

The castle appears to have met its end sometime in the 1740s. Smith’s historical accounts provide an intriguing timeline of its demise; in his 1746 history of Waterford, he describes the ruins as still standing, but by the time he published his history of Cork in 1750, he noted they had “very lately fallen down”. Local historian Waters suggests the collapse likely occurred between 1745 and 1749. Today, no trace of the once formidable structure remains above ground, leaving only historical records and old maps to mark where this FitzGerald stronghold once commanded the landscape.