What makes it unusual is not simply its age or origin, but what stands on it today: a concrete statue of the goddess Minerva, fixed upright in a rusty oil barrel. The combination is hard to account for and harder to forget.

The island, locally called Lady Island, is a crannog, a type of artificial or partially artificial island constructed in lakes and wetlands, most commonly during the early medieval period in Ireland. This one is described as a high-cairn type, built predominantly from small, fist-sized limestone stones, each roughly ten to fifteen centimetres in length, and laid with some consistency to produce a level upper surface and a gradual, even slope down to the waterline. A kerb of larger limestone blocks runs around the island at the water's edge, giving it a defined, almost formal boundary. The structure measures approximately 18 metres on its northeast to southwest axis and 14 metres across, rising to about 2.5 metres in height, and may have been built upon a natural rocky knoll rather than constructed entirely from scratch. It sits 440 metres northwest of where the River Brosna feeds into the lake, a location that would have made it both accessible and defensible in earlier centuries.

The Minerva statue introduces a note of deliberate oddness that no amount of archaeological description quite resolves. Minerva, the Roman goddess of wisdom and craft, has no obvious connection to this part of the Irish midlands, and the oil barrel plinth suggests the statue arrived relatively recently. Whether it was placed there as a joke, a piece of informal folk art, or something else entirely, the record does not say.