The 1908 Ordnance Survey six-inch map captured its final documented appearance, showing a rectangular area measuring approximately 50 metres northwest to southeast and 40 metres northeast to southwest. The site was enclosed by a fosse, a type of defensive ditch commonly used in medieval Ireland, with what appears to have been a leat, or artificial watercourse, running along its short southeastern side.

Moated sites like this one were a distinctive feature of the Anglo-Norman colonisation of Ireland during the 13th and 14th centuries. These fortified homesteads typically consisted of a raised platform surrounded by a water-filled moat, providing both defence and drainage for the settlers who established them. The rectangular shape and dimensions recorded at Coolyhune are characteristic of these sites, which served as rural strongholds for colonists adapting to life in what was often hostile territory.

Though the physical structure was levelled over sixty years ago, its brief documentation in historical records offers a glimpse into medieval settlement patterns in County Carlow. The information about this site comes from the Archaeological Inventory of County Carlow, originally published by the Stationery Office in Dublin in 1993, with updates incorporated from more recent archaeological research. Such inventories remain crucial for understanding Ireland’s medieval landscape, particularly for sites like Coolyhune that have been lost to modern development.