This one is remarkable for what does not. A ringfort once stood at Deerpark in County Kerry, a circular earthwork enclosure of the kind, known in Irish as a rath, that served as a defended farmstead during the early medieval period, roughly between the fifth and twelfth centuries. Today, not a single trace of it remains visible on the ground.

What makes the site particularly curious is its cartographic history. When the Ordnance Survey mapped this part of North Kerry in 1841 to 1842, no such enclosure was recorded. By the time a later edition of the map was produced in 1916, the ringfort had been noted. Whether it was overlooked in the original survey, identified through later fieldwork, or gradually became more legible in the intervening decades is unclear. What the maps together suggest is that the site was already fading from the landscape even as it was being formally recognised, and that by the twentieth century it had disappeared entirely from the surface. C. Toal's North Kerry Archaeological Survey, published in 1995, catalogued it as entry number 547, preserving at least a documentary record of something the land itself no longer shows.