The problem is that nobody can find it any more. The ground above it shows nothing; no hollow, no depression, no telltale dip in the grass to betray what lies beneath.

The site is known as Lisnakilla, or Lios na Cille in Irish, and it sits on a north-east facing slope less than a kilometre north of Anascaul village in County Kerry, about two hundred metres west of the Owenascaul river. It is a subrectangular enclosure of considerable size, and within its boundaries the foundations of several rectangular house sites are still visible at ground level. The souterrain, however, is another matter. It was discovered some years ago, its location recorded on the basis of local information, but by the time the Dingle Peninsula archaeological survey was compiled by J. Cuppage in 1986, no surface trace of it remained. Whatever clues once marked its presence have since vanished, leaving a known but effectively invisible feature, catalogued and referenced but impossible to locate without excavation.

There is something quietly strange about a place that is simultaneously documented and lost. The enclosure itself, with its faint house foundations, is the kind of early settlement landscape that survives in dozens of forms across the Dingle Peninsula, a region dense with prehistoric and early Christian remains. But most such sites offer at least something to see. Here, the most archaeologically specific feature, the souterrain, exists only as a fact on record, its precise whereabouts known to no one currently living who has been able to confirm it on the ground.