Yet the ground beneath it holds evidence of copper extraction stretching across more than four thousand years, from the earliest tentative experiments in metallurgy at the end of the Neolithic period right through to the early nineteenth century. Three distinct phases of mining have been identified here through excavation and survey, and the layers sit one atop another in a compressed, quietly extraordinary sequence.

The oldest workings, known locally as the Dane's Mines, a name that reflects centuries of puzzlement rather than any actual Scandinavian connection, date to roughly 2400 to 1900 BC, placing them among the earliest copper mines known in Ireland or Britain. Beaker people, named for the distinctive pottery style associated with their culture, worked the ore here and left behind not just diggings but a settlement, including huts and ore-processing areas on a limestone shelf above one of the mine openings. That settlement is no longer visible, but the workings themselves partially survive. The Blue Hole in the eastern sector is a trench-like opening running 68 metres long and up to 15 metres wide, and a cave-like entrance in the western area still yawns 10.5 metres across at its mouth before narrowing steeply inward. Centuries later, between around 650 and 725 AD, Early Christian communities were smelting copper here again, leaving furnaces and slag deposits at four locations underground, none of them visible at the surface. Then, from 1707 onward, the Kenmare estate began prospecting the same deposit in a more systematic way. Industrial-scale operations ran from 1804 to 1829, extracting around 5,000 tons of copper ore and shipping it to smelters in Swansea. The enterprise ended through a combination of commercial pressure and persistent flooding from the lough. What followed was an act of deliberate erasure: the Kenmare estate infilled the mine shafts and demolished the buildings, which had included engine houses, a powder magazine, an assay office, a barracks, and a manager's house. None of those structures survives above ground, though foundations are traceable in places.

Visitors walking the Ross Island paths today pass over this layered history largely unannounced. The Blue Hole is the most legible surviving feature, and the partly flooded and infilled shafts, quarry faces, and mine dams from the post-medieval period are scattered across the landscape. The cave-like Bronze Age opening in the western area can be found, though its interior is now heavily silted and almost fully blocked at the back wall.