Walk the field today and you would notice almost nothing out of place, perhaps a faint rise in the ground that could easily be mistaken for natural variation in the soil. The structure that once stood here has been levelled entirely by centuries of agricultural work.

The site sits on a north-facing slope near the crest of a hill in gently rolling terrain, and its existence was effectively erased from the mapped record before cartographers even had a chance to capture it properly. The first edition of the Ordnance Survey six-inch map, produced around 1840, makes no mention of it at all. By the time the second edition was compiled in 1904 to 1905, surveyors could only note it as Lisnamuck, with the telling qualification "Site of", indicating that even then it was understood to be gone rather than standing. What brought it back into view, however briefly and in ghostly form, was an aerial photograph taken on 16 July 1989. In the right conditions, buried ditches and banks alter how crops grow above them, producing crop marks, variations in colour and height that are invisible at ground level but legible from the air. The 1989 photograph revealed the cropmark of a curvilinear enclosure defined by a fosse, a ditch cut into the earth as a boundary, with a narrower concentric outer fosse running around it. Two roughly circular ditches, one inside the other, are the signature of a site that was deliberately and carefully bounded.