Notes: "Llanymynech is a village straddling the border between Powys, Wales, and Shropshire, England, about 9 miles (14 km) north of the Welsh town of Welshpool, according to Wikipedia. "Llanymynech Hill is one of Wales' earliest mining sites. Evidence suggests that copper was mined and smelted here in the late Bronze Age, and that ores were used for the manufacture of bronze weapons and other implements."
"Bones believed to be the remains of a human" were found in these caves by two men exploring with metal detectors in 2014, according to the BBC.
"The site was in use for copper mining over 4,000 years ago and was taken over by Romans when they arrived in Britain."