They are neither. These platforms, each roughly nine metres long and six metres wide, are the physical signatures of charcoal production, an industry that leaves almost no written record but a very legible mark on the land.

Charcoal was made by stacking wood into a carefully constructed mound, covering it with turf or earth to restrict airflow, and burning it slowly over several days. The process required a level working surface, which is why charcoal burners, known in parts of Europe as colliers, cut and packed these oval platforms into sloped ground. At Lugduff, more than seventy such platforms have been recorded at irregular intervals along the northern and southern shores of the Upper Lake and to the west and south-west of Reefert Church, the ruined early medieval church that sits within the Glendalough monastic valley. A further forty similar platforms were noted separately, bringing the total count well above a hundred across the area. The sites were documented by Ua Riain in 1940 and later by Healy in 1972, though the industry itself likely dates to a period when local ironworking or other fuel-hungry trades created sustained demand for charcoal in the valley.

The platforms are not easily visible as industrial features to an untrained eye, which is part of what makes them quietly interesting. Walking the paths around the Upper Lake, a visitor who knows what to look for will begin to notice the regularity of these subtle earthworks appearing at intervals through the trees and scrub, each one a small, deliberate reshaping of the hillside that speaks to an organised and repeated practice rather than any single event.