Part of the plateway system connecting various ironstone and coal levels on the NE slope of Mynydd Aberd're with Cyfarthfa Ironworks.
(SO03720665-SO03440659).

1884 (OS 6-inch 1st Edn.): this section was composed of two separate lines running eastwards from SO03440659, the northern line running to transhipment with a standard-gauge siding; the southern one running to the Cyfarthfa Iron Works to connect with the internal plateway system.

1905 (OS 6-inch 2nd Edn.): the southern line had been cut back to serve a tipping stage on the standard gauge sidings.