Built sometime before 1683, when it first appeared on Petty’s map of Kerry, this rectangular tower house measured approximately 9 by 7.5 metres. Local tradition attributes its construction to the Ferriter family, though its final resident was Admiral Moriarty, who died around 1810. A stone bearing the date 1694 was removed from the site in the early 19th century, offering a tantalising clue to the castle’s timeline, though this artefact has since vanished.

By 1841, three walls of the keep still stood to an impressive height of six metres, with remnants of a staircase visible in the southwest corner and six square windows punctuating the stonework. However, the castle’s decline was swift; within fourteen years, nearly the entire structure had collapsed, leaving only a small section of wall standing. Today, no trace of the castle remains in the old village of Ballineanig, its stones likely repurposed for local building projects or simply weathered away by centuries of Atlantic storms.

The castle’s location at Smerwick Harbour places it within a historically significant landscape. This area of the Dingle Peninsula saw considerable maritime activity and conflict over the centuries, with the harbour serving as both a refuge and strategic point for various military and trading ventures. Though Ballineanig Castle has disappeared from the physical landscape, its brief appearances in historical records offer glimpses into the lives of the minor gentry who once controlled these coastal strongholds along Ireland’s western edge.