Fforest Fawr and the Swansea Valley

Powys reaches a long way further south-west than most people expect. The county boundary runs down the Tawe almost to Ystalyfera, taking in the upper Swansea Valley and the limestone country of Fforest Fawr with it.

This corner has more in common with industrial south Wales than with the rest of the county, and it is the most strongly Welsh-speaking part of Powys by some distance. It is also, consistently, the part left out of county-wide accounts, which is a gap worth correcting.

What to look for

Anthracite. The upper Tawe sits on the western coalfield, and the collieries and their spoil shaped every settlement between Abercraf and Ystradgynlais.

Ynyscedwyn ironworks at Ystradgynlais, where iron was first successfully smelted with anthracite in 1837, a process that transferred to Pennsylvania and helped industrialise the United States.

Limestone. Caves at Dan yr Ogof and Ogof Ffynnon Ddu, the latter among the deepest cave systems in Britain, and quarries and lime kilns across the escarpment.

Waterfall country around Ystradfellte, where the Mellte, Hepste and Nedd Fechan cut gorges through the same limestone.

Bilingual signage that is not tokenistic, and chapels that still hold Welsh-language services.