This one does neither. On a south-facing slope of a drumlin in Gortnalug, a ringfort lies completely invisible to anyone standing in the field above it. No earthwork breaks the pasture, no ridge or hollow betrays its outline. It exists, as far as ground-level observation is concerned, not at all.

A ringfort, or rath, is one of the most common monuments in the Irish landscape, a roughly circular enclosure defined by one or more banks and ditches, used as a farmstead during the early medieval period, roughly 500 to 1000 AD. Thousands survive across the country in various states of preservation. This one in Gortnalug is unusual precisely because it has survived in no visible state whatsoever. It does not appear on any Ordnance Survey map, and is absent from most aerial imagery. It was identified from a specific set of aerial photographs, where a circular enclosure of approximately 25 metres in diameter becomes discernible on the slope of the drumlin, a drumlin being one of those elongated, smoothed hills left behind by retreating glaciers and found throughout counties like Leitrim in considerable numbers. That a monument of early medieval origin could shelter on such a landform and escape both cartographic record and casual aerial detection gives some sense of how much the Irish landscape may still conceal.