Hendre Ddu slate quarry opened in the 1850s, and in 1864 the Hendre Ddu Slate and Slab Co. was established by Sir Edmund Buckley. The Company specialised in slate slabs for billiard table beds.
The standard gauge Mawddwy Railway, opened in 1867 connected the Cambrian Railway at Cemmaes Road to Dinas Mawddwy, passing through the small village of Aberangell. Sir Edmund Buckley built the Hendre Ddu Tramway to carry slate from his quarry down to Aberangell station. Several other quarries had branches and spurs onto the Tramway, as well as a brickworks, a sawmill and several local farms.
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The GR is for Aberangell