The ringfort at Killeenavera in County Limerick falls into that category. A rath, as these circular earthwork enclosures are commonly known in Ireland, was typically the farmstead of an early medieval family, defined by one or more earthen banks and ditches and serving as both a domestic space and a marker of social standing in the landscape. By 1964, this one was still substantial enough to measure and draw. By 2002, aerial imagery shows it had been absorbed entirely into a disused quarry cut into the hillock on which it stood.

When O'Dwyer documented the site in 1964, he recorded a well preserved circular platform roughly 26.5 metres in diameter and 1.5 metres high, defined on its southern, western, and northern sides by a fosse, the term for the ditch that typically accompanies such earthworks, around 1.8 metres wide. O'Dwyer noted that the monument occupied a commanding position in the landscape, which is consistent with the elevated hillock setting. The rath had already appeared on the 1897 edition of the Ordnance Survey 25-inch map as a clearly defined circular platform, confirming its survival into the early twentieth century in recognisable form. When the Archaeological Survey of Ireland revisited the site in 2008, surveyors recorded no surface remains visible. Quarrying of the hillock had done what centuries had not. A possible barrow, a type of prehistoric burial mound, lies approximately 50 metres to the north-east, and Killeenavera House stands around 200 metres to the east-north-east.

For anyone curious enough to look, later satellite imagery taken between 2005 and 2018 shows the former location of the rath as a cluster of trees within the disused quarry, a faint botanical trace where the earthwork once stood. There is nothing to see at ground level, and no formal access point is noted for the site. The interest here is less in visiting than in the process of looking across sources, comparing O'Dwyer's 1964 profile drawing against aerial orthoimages from 2002 and 2018, and watching a monument disappear across the decades in a way that the documentary record preserves even when the ground no longer does.