A small circular enclosure, the kind of mark that archaeologists spend careers learning to read from the air, appeared clearly in a photograph taken in July 2006. When someone went to look for it on the ground seven years later, there was nothing to find.

Circular enclosures in Ireland range from prehistoric ring forts to early medieval farmsteads, and they survive in the landscape in all sorts of conditions, from well-preserved earthen banks to the faintest soil discolourations visible only from above. This one belongs firmly to the latter category, and arguably not even that. Crop marks and parch marks, the shadows that buried or levelled features cast in dry summers when grass or grain grows unevenly over disturbed ground, can appear and vanish depending on the season, the weather, and the depth of whatever lies beneath. The 2006 photograph caught something. The 2013 inspection found nothing. Whether the feature is genuinely buried, completely ploughed out, or simply waiting for the right conditions to reappear is not recorded.