Nothing breaks the surface. No stone, no mound, no earthwork gives any hint that something once stood here. Yet aerial photography taken in 2018 caught what ground-level inspection cannot: a clear cropmark tracing the full circular outline of a ring barrow that was bulldozed out of existence sometime after the mid-twentieth century.

A ring barrow is a burial monument of prehistoric origin, typically consisting of a central mound raised over human remains, encircled by a ditch, known as a fosse, and an outer earthen bank. The Ballybaun example was recorded by McCaffrey in 1952 and again in 1955, who described a circular monument approximately 37 metres in overall diameter. At its centre sat a low, flat-topped mound some 17.7 metres across and around 0.42 metres high, the whole enclosed by a fosse and external bank in the usual fashion. The site lay in farmland, roughly 40 metres to the south-east of a rath, the circular enclosure type commonly associated with early medieval settlement in Ireland, suggesting this area had a long sequence of human activity. At some point after McCaffrey's visits, the monument was levelled by machine, and no physical trace remains above ground.

What makes the Ballybaun barrow quietly remarkable now is precisely its absence. Cropmarks form when buried features, ditches that retain moisture or compacted soil that drains it faster, influence the growth of crops or grass above them, producing visible variations in colour and height that are legible only from the air. The 2018 aerial imagery effectively recovered a monument that had been deliberately erased, outlining in the summer growth of a Galway field the shape of something that had stood for perhaps three thousand years before a single afternoon's machinery work.