This one is defined entirely by what does not. At Cappanacush in County Kerry, a ringfort once occupied a natural rise above marshy ground, positioned to look out over Kenmare Bay to the south. A ringfort, or rath, is a roughly circular earthen enclosure, typically dating from the early medieval period and used as a farmstead or place of refuge. This particular example has left nothing visible above ground. No bank, no ditch, no hollow in the turf. It exists now only as a map notation and a name in old records.

The site appears clearly enough on the first edition of the Ordnance Survey map, drawn in the nineteenth century, where it is rendered as a circular enclosure. By the time the second edition was produced, the cartographers had downgraded it to a simple "site of", the quiet cartographic admission that something once present can no longer be confirmed. What makes the Cappanacush example particularly intriguing is a note in the Ordnance Survey Name Books, which records it not merely as a fort but as a "fort with a cave in it", suggesting a souterrain, an underground stone-lined passage commonly built beneath early medieval settlements for storage or shelter, may once have been associated with the enclosure. That detail is tantalising precisely because there is now no physical evidence left to examine. A. O'Sullivan and J. Sheehan documented it in their 1996 archaeological survey of the Iveragh Peninsula, pulling together what the historical record could still offer about a feature the landscape itself had already erased.