At Brickendown in County Tipperary, a small oval enclosure sits within the interior of a moated site, a type of monument common in medieval Ireland in which a raised platform or island was surrounded by a water-filled ditch, often associated with high-status rural settlement. That a distinct secondary enclosure should be found inside such a feature is what makes this spot quietly odd, a structure within a structure, each apparently serving different purposes across what may have been a considerable stretch of time.

The enclosure itself is modest in scale, roughly 25 metres along its longer northeast-to-southwest axis and 14 metres across, defined by a low scarp rather than a dramatic wall or bank. A roughly linear earthen bank runs parallel to the southeastern side and includes a short return at its southeastern end, creating what surveyors identified as a narrow passage between bank and monument. That passage may be connected to quarrying activity, and there is firmer evidence of quarrying along the northeastern arc of the enclosure, where a section measuring about 16 metres north to south and 6 metres east to west has been cut to a depth of more than 2 metres. The quarrying is described as ancient, though its precise date is unknown. The interior surface is uneven, scattered with occasional small stones, and the southern portion of the site shows signs of more recent agricultural use, with evidence of ring feeders suggesting cattle were over-wintered there at some point.