At Ballyhomin in County Limerick, a ringfort once occupied a west-facing slope below the brow of a low hill, its circular earthen bank enclosing a space of roughly thirty metres in diameter. By the time anyone came to record it formally, it was already gone.

Ringforts, known in Irish as raths, were the most common form of rural settlement in early medieval Ireland, typically consisting of a circular area enclosed by one or more earthen banks and ditches, used as a farmstead and enclosure for livestock. This one at Ballyhomin was recorded on the Ordnance Survey six-inch map of 1841, depicted as an embanked circular enclosure, which means it was still visible, at least in outline, when the surveyors passed through. At around thirty metres across, it would have been a modest but recognisable example of the type. At some point between that mapping and the site inspection compiled by Denis Power in August 2011, the monument was levelled entirely. When Power visited, the paddock field on that gentle hillside showed no trace of it whatsoever.

This is, in its own way, a common story. Agricultural improvement, ploughing, and land drainage have erased thousands of ringforts from the Irish countryside since the nineteenth century, and the 1841 map record is often all that survives. For anyone curious enough to visit Ballyhomin, the landscape itself is unremarkable in the way that erased history tends to be: a paddock on a slope, a hill brow above it, nothing obviously out of place. The coordinates attached to the record will bring you to the general area, but there is nothing on the ground to find. The interest here lies less in what you might see than in the habit of reading the land against old maps, learning to notice where something once was by the faint logic of its setting, a sheltered slope, a slight elevation, a view to the west.