This earthwork fortification consists of a raised rectangular platform surrounded by a water-filled ditch, or moat, which would have once protected a timber hall or farmstead. Dating from the 13th or 14th century, the site likely belonged to an Anglo-Norman settler or a prosperous Irish family adapting Norman building techniques during a period when such fortified homesteads dotted the landscape of south-east Ireland.

What makes Listerlin particularly interesting is its excellent state of preservation; the moat still retains water for much of the year, and the raised platform remains clearly defined despite centuries of weathering. The site measures approximately 40 metres square, with the surrounding ditch averaging 10 metres in width. This scale suggests it housed a substantial dwelling, possibly with additional outbuildings for livestock and storage. Archaeological evidence from similar sites indicates these moated settlements served multiple purposes: defence against cattle raids, status symbols for their owners, and practical solutions for drainage in low-lying areas.

Today, the Listerlin moated site stands in quiet farmland, its defensive purpose long forgotten but its earthworks still impressive. These monuments represent a transitional period in Irish history when Norman colonists and Gaelic Irish were creating a unique hybrid culture. While stone castles capture the imagination with their towers and battlements, these humbler earthwork sites tell the story of everyday life in medieval Ireland; farmers and merchants who needed protection but couldn’t afford stone fortifications, yet still managed to leave their mark on the landscape seven centuries later.