In the townland of Fortyacres in County Galway, the nineteenth-century Ordnance Survey six-inch maps record a small circular mound roughly twenty metres in diameter, sitting some thirty metres to the south-east of a nearby enclosure. No visible surface trace survives today. The mound has, in effect, disappeared into the field.

Circular earthen mounds of this kind are a broad category in the Irish archaeological record, and their purposes varied considerably, ranging from burial cairns and platform mounds to the levelled remnants of ringforts or other enclosures. What made this particular feature worth recording was its proximity to the adjacent enclosure, suggesting the two may once have formed part of a related complex of activity on the same piece of ground. The Ordnance Survey cartographers who mapped it in the nineteenth century captured it at a moment when it was still legible in the landscape, even if only barely so. By the time the Archaeological Inventory of County Galway, compiled by Olive Alcock, Kathy de hÓra, and Paul Gosling, was published in 1999, the mound had left no mark above the surface at all.