The Halkyn Mines encountered a number of natural passages and chambers: Powells Lode and Barclays Caverns; Halkyn Lode, Cornel-y-cae, and Lode 621 Chambers; Lode 716 Cave; Rhosesmor Feeder; Wern Sump and Wern Aven; Cathole and Llyn-y-pandy Lodes; Halkyn Tunnel and Pant Lode Vughs
Controlled by GCC Warden. An entrance to the Halkyn Mines.
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(1997); CATMHS - Newsletter 051-October; 20 pages
Jones, Nigel and Walters, Mark and Frost, Pat (2004); Mountains and Orefields; 208 pages
Rhodes, J.N. (1968); PDMHS (Peak District Mines Historical Society) 03-6 - Derbyshire Influences on Lead Mining in North Wales in the 17th and 18th Centuries; 13 pages (339-351)
Williams, C.J. (2001); PDMHS (Peak District Mines Historical Society) 14-6 Win - Mining Laws in North Wales, The; 3 pages (67-69)