Ringforts, known in Irish as raths, are among the most common archaeological features in the Irish landscape, typically dating from the early medieval period, roughly 500 to 1000 AD, and built as enclosed farmsteads for a single family or small community. Most have been ploughed flat, built over, or swallowed by scrub. This one survives with unusual clarity.

The enclosure at Garryduff is roughly circular, measuring 48.8 metres north to south and 46.4 metres east to west, and it sits in level marshy pasture, the kind of ground that may have helped preserve it simply by discouraging intensive tillage. The earthen bank that defines it stands about half a metre above the interior ground level, but rises to 1.7 metres on the outer face, giving it considerably more presence when approached from outside. Beyond the bank runs an external fosse, a defensive or drainage ditch, here roughly 0.6 metres deep and 2.7 metres wide. The main entrance, nearly four metres across, opens through the bank at the south-west, which is a common orientation for ringfort entrances in Ireland, possibly for reasons of shelter or solar alignment. There are also narrower gaps in the bank to the north-north-west, north-east, and east-south-east, though whether these are original features or later breaks is not recorded in the survey compiled by Denis Power.

The interior is level, dry, and largely free of overgrowth, which makes it easier than many ringforts to read the shape of the place and get a sense of the enclosed space that once constituted someone's domestic world. There are no signposts or formal access arrangements noted for this site, and it sits within working agricultural land, so any visit should be approached with the usual consideration for farm gates, livestock, and ground conditions. The marshy pasture that surrounds it means the approach can be soft underfoot, particularly in wetter months. Looking at the bank from outside the fosse gives the clearest impression of its original defensive profile, modest by any martial standard, but enough to mark a boundary and signal occupation.