Locals in Ballynacorra, Co. Galway, have long called it the "fort field", and the reason is still just visible underfoot, even if only barely. Beneath the grass on a gentle rise in otherwise level ground, a subcircular rath survives in a degraded state, its outline tracing an oval roughly 55 metres north to south and 43 metres east to west. A rath is an early medieval enclosure, typically of earthen construction, that once defined the farmstead of a landowning family, and this one would have been a substantial example in its day.

What survives now is defined principally by a scarp, the eroded edge of what was once a more pronounced bank, and an external fosse, the shallow trench that would originally have ringed the interior. At the south-east there is a possible entrance gap measuring around 5.5 metres in width, which aligns with the convention of orienting rath entrances towards the south or east. The monument has not come through the centuries intact. Quarrying has removed material at the north and south-west, and a field boundary cuts across the southern side, both of which account for the irregular and subdued appearance of what remains. Despite all of this, the local memory encoded in the field's name has proved more durable than the earthwork itself.