At Ballynaguila in County Limerick, a ringfort that was still mappable in the 1920s has since been erased so completely that an inspector found no trace of it whatsoever. That absence is itself a kind of information, a small, quiet record of how much the Irish landscape has been altered by the ordinary business of farming.

A rath, to use the Irish term, is an early medieval farmstead enclosed by one or more earthen banks and ditches, typically circular or near-circular in plan. The example at Ballynaguila was recorded on the 1923 Ordnance Survey six-inch map as a penannular enclosure, meaning a ring broken by a single gap, most likely the original entrance. Its diameter was approximately thirty metres, which is fairly typical for a single-ringed example. It sat at the western end of a low ridge in an area of outcropping limestone, the kind of well-drained, elevated ground that early farmers tended to favour. When Denis Power compiled his inspection notes, uploaded in August 2011, the monument had been levelled, leaving pasture where the earthworks once stood.

For anyone curious enough to visit, the location is in open farmland and the ground is likely grazed. Because the earthworks have been entirely removed, there is nothing visible to orient yourself by. The outcropping limestone in the surrounding area remains, and the ridge itself can still be read in the topography, but the enclosure that once occupied its western end is gone. The 1923 OS map is the most useful document here, showing the monument at a moment when it could still be recorded. Comparing that sheet with the current ground is, in its own way, the whole point of the visit.