That inaccessibility is not merely inconvenient; it is, in a sense, the point. The island is a crannog, an artificial or artificially modified island dwelling built out into a lake, typically during the early medieval period in Ireland, and used as a defensible homestead. The reeds that now frustrate any approach were once, in a different form, part of the logic of such places.

What is curious about this particular site is how quietly it disappeared from the cartographic record. Funshinagh Lough itself is a modest oval body of water, roughly 280 metres from north to south and 150 metres from east to west, and the crannog appears on the Ordnance Survey six-inch map of 1911. It is not depicted on earlier editions of that map series, which raises a question that the surviving evidence does not quite answer: whether the island was overlooked by earlier surveyors, whether vegetation or water levels obscured it at certain periods, or whether its recognition as a distinct feature simply came late. The 1911 appearance is the only cartographic moment in which it is formally acknowledged.