This medieval earthwork consists of a raised square platform measuring 52 metres from north to south and 49 metres from east to west, defined by a scarp that rises between one and one and a half metres high. A modern gap, about six and a half metres wide, breaks through the western side of the platform, whilst traces of what was once a shallow outer fosse, or defensive ditch, can still be detected around the perimeter.

The site has undergone significant changes since its medieval heyday. A nineteenth-century farmhouse now stands adjacent to the platform, with its garden enclosure extending to the south and southeast. The field boundary that currently encloses the platform appears to date from the same period as the farmhouse, suggesting that the medieval earthwork was incorporated into the farm’s layout during the 1800s. This layering of different historical periods is quite typical of Irish rural landscapes, where medieval fortifications often became part of later agricultural holdings.

Moated sites like this one were typically constructed by Anglo-Norman colonists or wealthy Gaelic families during the thirteenth and fourteenth centuries. They served as fortified homesteads; the raised platform would have supported timber buildings, whilst the surrounding fosse provided both drainage and a defensive barrier. The square shape and substantial dimensions of the Longfordpass South example suggest it was home to someone of considerable local importance, though the exact identity of its medieval inhabitants remains unknown.