On the south-western shore of the King's Channel, a looping detour the River Suir makes through County Waterford, there is a country house whose walls contain older walls, and whose history keeps doubling back on itself. What presents itself as a relatively orderly rectangular residence of five bays, two floors, and an attic is, in fact, a later structure built around the bones of a much earlier tower house. A tower house was a form of fortified dwelling common in late medieval Ireland, essentially a tall, narrow defensible residence of the kind that once punctuated the landscape in considerable numbers. At Ballynakill, rather than being cleared away, the earlier structure was absorbed into the later building, giving the house a layered character that renovations have periodically confirmed.

By 1640, the property was recorded as a decayed castle in the ownership of the Dobbin family, a description that suggests the medieval structure had already fallen into disrepair well before the present house took shape. The rectangular house is thought to date from the late seventeenth century, and the discovery of a seventeenth-century fireplace during renovation work lends some physical weight to that dating. Whether the Dobbins were responsible for the later construction or whether the property passed to other hands before it was rebuilt is not clear from what survives. Just to the south-south-east of the house, an adjacent church site adds another layer to the immediate surroundings, suggesting that the area around this bend in the river carried some local significance well before either the castle or the house were built.