What survives of this ringfort, or rath, a type of enclosed farmstead typically built during the first millennium AD, is enough to trace the idea of it, though only just.

A rath of this kind would originally have consisted of a roughly circular earthen bank enclosing a domestic space, with a single entrance gap and a cleared interior where a family and their livestock might have lived. At Garrynagore, that enclosure measured approximately 42.6 metres across its interior from north to south, making it a reasonably substantial example. The enclosing bank has been heavily levelled over the centuries and, where it has not been swallowed entirely by later field fences running from the north-west around through the west and south, it rises no more than 1.5 metres above the surrounding ground. The original entrance was reportedly to the south-east, according to the landowner at the time of survey, though nothing of it remains visible. Within the northern part of the interior sits a small internal mound, measuring roughly 3.2 metres east to west and 2.4 metres north to south, and standing about 0.9 metres high. Its purpose is not recorded, though internal mounds within raths can sometimes indicate the site of a former structure or, in some cases, a souterrain, an underground stone-lined passage used for storage or refuge.

The condition of the site reflects a process that has affected hundreds of similar monuments across Ireland, where field enclosure over recent centuries gradually incorporated ancient earthworks into working farm infrastructure, leaving only fragments for later surveyors to piece together.