1. A plateway system connecting various ironstone and coal levels on the NE slope of Mynydd Aberdare with Cyfarthfa Ironworks.
By 1884 (OS 6-inch 1st Edn.) the system consisted of three main routes, each with branches:
i) Westwards, parallel and to the south of the Merthyr-Hirwaun road.
ii) South and west to serve the higher slopes of Mynydd Aberd're.
iii) Southwards to serve levels along the western slope of the Taff valley.
The system connected with the internal plateway system of Cyfarthfa Ironworks.
By 1905 (OS 6-inch 1st Edn.) most of the southern limb (iii) had gone and the other two routes had been cut back, but several new branches had been added. The system no longer ran into the ironworks but connected with a transhipment point on a standard gauge siding.
Measurements between plate marks on surviving stone blocks indicate a gauge of about three feet.
D.J.Percival, RCAHMW, 31 October 1994.

2. Steeply-dropping route of mineral line from Winch Fawr to Cyfarthfa Iron Works. A good section of the route is visible at Heolgerrig (SO 031062).
(A Guide to the Industrial Archaeology of South East Wales, AIA, 2003)
B.A.Malaws, RCAHMW, 03 June 2010.