They are, in fact, the physical traces of charcoal production, an industrial process that once left its mark quietly across wooded upland valleys throughout Ireland and Britain. Each platform, roughly nine metres by six metres, was where a collier would build and tend a slow-burning wood pile, sealed under earth and turf to char timber into charcoal with minimal oxygen. The method required flat, stable ground, which is why these artificial shelves were cut and levelled into slopes in the first place.

Around Lugduff, in the valley of Glendalough in County Wicklow, more than seventy of these platforms have been recorded, arranged at irregular intervals along the northern and southern sides of the Upper Lake and to the west and south-west of Reefert Church, a small Romanesque ruin associated with the early monastic settlement of the valley. The platforms were noted by Ua Riain in 1940, and further recorded by Healy in 1972, who documented around forty examples of comparable form. The number and distribution suggest sustained, organised production rather than occasional or casual burning, pointing to an industry that likely served ironworking or domestic fuel demand in the region, though the precise period of use is not recorded. The wooded slopes of Glendalough would have provided ample raw material, and the valley's relative isolation made it well suited to the kind of slow, labour-intensive work that charcoal-making required.