At Knockbrack East, a large rath sits on gently sloping farmland, its earthworks so worn in places that the site is known almost entirely from maps and aerial photography rather than anything obviously visible at ground level. What survives is uneven: a bank still readable along the northern and western arc, tapering to a mere scarp on the southern and south-eastern sides, and levelled away entirely elsewhere. An external fosse, the defensive ditch that would originally have ringed the outer edge of the enclosure, remains traceable from the north-east around to the east. The interior diameter runs to approximately 65 metres, which places this among the larger examples of its type.

Ringforts, known in Irish as raths when defined by earthen banks rather than stone, were the dominant settlement form of early medieval Ireland, typically serving as enclosed farmsteads for a single family and their livestock. Most date to roughly the sixth through twelfth centuries, though the form persisted longer in some areas. The Knockbrack East example was already being recorded cartographically by the time of the first Ordnance Survey six-inch map in 1840, which depicts it as a large circular enclosure. More recently, aerial photography from the Ordnance Survey Ireland archive has revealed something potentially more complex: the faintest suggestion of a smaller central enclosure, roughly 25 metres in diameter, set within the main monument. Whether this represents a structural feature of the original design or a later addition is unclear, and the site has not been examined through excavation. The record was compiled by Edmond O'Donovan and uploaded to the national monuments database in July 2020, drawing on cartographic and aerial photographic sources alone.

The rath lies approximately 90 metres south of the townland boundary with Drominboy Upper, and around 490 metres west of a standing stone on the summit of Knocksentry Hill, so there is a modest concentration of early monuments in this corner of County Limerick worth bearing in mind. Access is across private farmland, so permission from the landowner would be needed before approaching the site on foot. The clearest overall impression of the monument comes not from ground level but from Google Earth, where orthophotography captured in June 2018 shows the tree-lined outline of the enclosure with surprising clarity. The field entrance at the south-east may follow the line of the original entrance through the bank, which is a detail easy to overlook but oddly satisfying once noticed.