In the low-lying pasture at Ballywilliam in County Limerick, a ringfort once stood near the base of a west-facing slope, and the only reliable evidence that it was ever there at all is a line drawing on a survey sheet from 1923.

Ringforts, sometimes called raths, are among the most common archaeological monument types in Ireland, typically consisting of a circular area enclosed by one or more earthen banks and ditches. They were built and used mainly during the early medieval period, functioning as farmsteads and settlement enclosures. The Ballywilliam example was recorded on the Ordnance Survey six-inch map of 1923 as a circular embanked enclosure roughly thirty-five metres in diameter, which is a fairly typical scale for such a structure. At some point between that survey and a more recent inspection compiled by Denis Power and uploaded in August 2011, the monument was levelled entirely. When Power visited, no trace of it remained visible.

The loss of earthworks like this one is not unusual in agricultural landscapes, where ploughing, drainage work, and general land improvement have quietly removed thousands of monuments across the country over the course of the twentieth century. What makes this particular case worth noting is the precision of its documentation and the completeness of its disappearance. A visitor to the field at Ballywilliam today would find only ordinary pasture, with nothing to indicate that a structure once enclosed this patch of ground. The 1923 map remains the clearest record of what was here. If you are drawn to the site regardless, it lies in flat grazing land near the foot of a westward slope, though there is nothing on the surface to orient yourself by.