This one is notable for what cannot. At Glanerdalliv in north County Kerry, a place once known as Lissacurrig, or Lios Uí Coruig, meaning O'Corick's fort, a circular enclosure once stood in the landscape, and somewhere within it, a souterrain lay concealed beneath the ground. A souterrain is an underground stone-lined passage or chamber, typically built during the early medieval period and associated with nearby settlements or ringforts, used variously for storage, refuge, or both. By the time the later Ordnance Survey maps were drawn in 1915 and 1916, the cave marked so clearly on the 1841 to 1842 edition had already disappeared from the record. Today, the enclosure itself has been levelled entirely, and no trace of either feature survives above or below the surface.

The site sits to the south-east of a related enclosure recorded nearby, and its double appearance on successive Ordnance Survey editions offers a small window into how quickly such places can slip from visibility. The earlier maps, produced in the 1840s, were among the most detailed surveys of the Irish landscape ever undertaken, and their notation of a cave within the fort suggests the souterrain was still identifiable, perhaps still partially open, at that time. That it was omitted from the revised survey some seventy years later implies it had already been filled, collapsed, or simply forgotten in the intervening decades. C. Toal's North Kerry Archaeological Survey, published in 1995, records the site's existence while noting its obliteration, preserving at least the placename and its rough location for the historical record.