What makes this particular example quietly puzzling is that no original entrance can be identified. Most ringforts preserve at least a gap or causeway that hints at how people and animals once moved in and out, but here that evidence has either vanished entirely or was never obvious to begin with.

The enclosure at Lyonstown measures twenty-nine metres across in both directions, making it a modest but coherent circle. It is defined by an earthen bank, between 1.6 and 2.4 metres wide, that survives to only a modest height, between about ten and fifty-five centimetres above the interior ground level depending on where you measure. On the outside, the bank rises slightly more consistently, to around half a metre. A fosse, which is simply a ditch dug to reinforce the barrier and from which the bank material was likely quarried, runs around much of the perimeter, though it too is shallow, no more than ten centimetres deep externally in the sections recorded. Part of the original bank has been absorbed into a later field boundary on the north and north-north-east side, which is a common fate for these structures as agricultural patterns shifted across the centuries and farmers found it practical to incorporate existing earthworks rather than flatten them.