What appears at first glance to be a late eighteenth-century house with Gothic Revival flourishes actually conceals something much older; the bones of a rectangular tower house that once dominated this landscape centuries ago.

The original tower house reveals itself most clearly at ground level, particularly at the northern end of the building. Here, visitors can still trace the outline of the medieval structure through its impressively thick walls, measuring about 1.5 metres across, and the stone-flagged floors that have survived the centuries. Parts of an arrow loop remain visible in the eastern wall, alongside a mural staircase built directly into the stonework; both classic defensive features of Irish tower houses. Whilst a large fireplace and entrance in the northern wall likely date from the eighteenth-century renovations, they sit within the medieval framework like Georgian furniture in a Norman room.

Above ground floor, the evidence becomes more fragmentary but no less intriguing. The first floor shows traces of what might be another loop embrasure or perhaps a wall cupboard, though the eighteenth-century rebuilding has obscured much of the original layout. Notably absent is any sign of the barrel vaulting typical of many Irish tower houses, suggesting either it was never built or was removed during the later renovations. This blend of medieval military architecture and Georgian domestic comfort makes Castletown Castle a particularly interesting example of how Ireland’s fortified past was adapted and absorbed into the country’s later architectural traditions.