The ancient opencast mine of Twll y mwyn [transl.: mine pit or hole] was re-discovered
and excavated by miners working for the Crown Mineral Agent and antiquary Lewis Morris
in 1744. His thoughtful observations on the antiquity of mining here provides us
with the earliest description of the discovery of stone tools, fire-setting and primitive
mining in Britain (Bick & Davies 1991).
The mine lies at the north end of the powerful Darren Lode, and during the 19th century
this part of the vein was re-worked for copper and silver-lead ores (the Copper Level).
The site was surveyed and excavated by the EMRG in June 2005 (Timberlake, 2006.)
This returned Bronze Age dates from the edge of the opencast working.