What makes the example at Seafield in County Sligo quietly arresting is how precisely its modest scale has been documented against a backdrop of incremental loss. The entire monument spans just 15 metres in total diameter. At its centre sits a circular mound only 5 metres across and 40 centimetres high, encircled by a U-shaped fosse 2.70 metres wide and 35 centimetres deep, and beyond that a bank 2.30 metres wide and 40 centimetres high. These are not grand dimensions, and the site sits on flat ground rather than any commanding elevation, which makes the care taken to record its geometry all the more significant.

Researcher Timoney, writing in 1984, noted that the south side of the outer bank had already been disturbed by the construction of a modern field boundary, and that agricultural development had stripped away the upper portion of the bank and the mound itself across roughly the northwest third of the monument. Göran Burenhult, in an earlier survey from 1980, placed the site within a grouping he called Structure 13, Knocknahur North, though later work corrected that placename to Seafield. This cluster comprised five structures in total, and all of them returned very low phosphate values. Phosphate analysis is used by archaeologists to detect the residue of organic material, bone and refuse in particular, so consistently low readings across the group suggest either that the monuments were never heavily used for burial or settlement in ways that would leave such traces, or that whatever once lay within them has long since broken down beyond detection. The site, in other words, holds its purpose quietly.