That slight deviation is one of the clearest signs that something older and more significant lies beneath the grass on this north-east-facing slope near Shanbally.

What survives is a roughly circular earthwork, measuring just over thirty metres across, the remnant of an enclosure that has been largely ploughed out over the centuries. An enclosure of this type would originally have consisted of a raised earthen bank and an external fosse, which is a ditch dug to reinforce the boundary, creating a defined and defensible or ceremonial space. The bank is still faintly readable, broad but now very low, standing only eleven centimetres above the interior surface and twenty-six centimetres above the exterior ground level; the fosse alongside it is reduced to shallow traces nearly six metres wide. Ploughing has done its gradual work, but not quite finished it. The enclosure appears by name on a surveyed estate map drawn up in 1815 by John Longfield, recording the lands of one Jn Bagwell Esquire in the barony of Iffa and Offa. That a cartographer working in the early nineteenth century thought it worth marking suggests the feature was still legible then, perhaps more legible than it is now, and that it carried enough local significance to be included alongside more obviously functional landscape features.