Historical Ordnance Survey maps from 1842 and 1905 show it as a square enclosure measuring approximately 25 metres on each side, surrounded by a water-filled defensive ditch or fosse. By 1937, the site had evolved in the cartographic record, appearing as a raised platform with a well marked at the southern end of its eastern side. The entire complex, including its protective earthworks, originally covered an area of about 45 metres square.

The site met its end in the late 1960s when it was levelled for agricultural purposes, though traces of its former grandeur remain visible to the keen observer. The eastern side preserves the most substantial evidence, with a shallow fosse still discernible between what was the inner platform and an impressive outer earthen bank that rises two metres above the surrounding ground level. This bank is accompanied by a waterlogged external ditch about a metre deep. Along the southern boundary, only a small section of the outer bank survives at the eastern end, whilst the remainder of the southern, western and northern defences exist as subtle rises in the ground with shallow depressions marking where the external ditches once ran.

This moated site represents one of several such medieval fortifications in the area; another levelled example lies about 500 metres to the west-southwest. These structures, typically dating from the 13th to 15th centuries, were defensive homesteads of Anglo-Norman settlers or prosperous Irish families. The surviving earthworks at Garryduff have been incorporated into the modern field boundary system, ensuring that whilst the site itself may be largely lost, its footprint continues to shape the landscape centuries after its construction.