Limestone quarries for the three Merthyr ironworks: Plymouth (NW), Penydarren (W) and Dowlais (N and NE). Tramroad and railway connections can be followed; the Plymouth quarry marks the northern end of the Merthyr Tramroad.
(A Guide to the Industrial Archaeology of South East Wales, AIA, 2003)
See also Morlais Quarries East (nprn 88066).
B.A.Malaws, RCAHMW, 07 May 2010.