Measuring roughly 12.8 metres long and 5.5 metres wide, the structure is defined by a stony bank that has settled so gradually into the earth that it is now little more than a gentle rise in the turf. It is orientated northeast to southwest, and the southeast and southwest sides remain the most legible; the northeast side has all but dissolved back into the ground, and at the northwest corner someone, at some unknown point, dug a pit into the bank itself.

What makes the site quietly puzzling is its relationship to a nearby enclosure sitting roughly 2.7 metres to the east. An enclosure, in this context, is typically a defined area bounded by a bank or ditch, often associated with early medieval settlement or agriculture. Whether this rectangular structure belongs to the same period and the same people who built that enclosure, or whether it arrived later and independently, remains unresolved. A third structure of similar character lies to the south of the enclosure, which suggests this corner of Treanbaun was once busier and more organised than the current silence implies. The cluster of features hints at a landscape that was shaped, reshaped, and then gradually forgotten, though the sequence and purpose of each element have not yet been firmly established.