They are anything but. These are the remnants of a charcoal-making industry, and there are a remarkable number of them, more than a hundred recorded across the area, concentrated along the northern and southern shores of the Upper Lake and to the west and south-west of Reefert Church.

Charcoal production relied on carefully constructed hearths called pitsteads or charcoal platforms, where timber was stacked, covered with earth and turf to restrict airflow, and then slowly burned over several days. The resulting charcoal was a far more efficient fuel than raw wood and was essential for smelting iron and other industrial processes. The platforms here, each measuring roughly nine metres by six metres, are oval in shape and distributed at irregular intervals through the valley, suggesting organised, repeated use of the landscape over time rather than a single episode of activity. Ua Riain noted the presence of around seventy-five such platforms as early as 1940, with a further forty of similar form recorded by Healy in 1972, pointing to a site that had already drawn scholarly attention by the mid-twentieth century. Glendalough and its surrounds were long associated with monastic and later industrial activity, and the valley's timber resources would have made it a logical location for sustained charcoal production, though the precise period of operation is not firmly established from the available evidence.