River Neath

River Neath is a river in south Wales running south west from the point at which its headwaters arising in the Brecon Beacons National Park converge to its mouth at Baglan Bay below Briton Ferry on the east side of Swansea Bay.

The rivers Nedd Fechan, Mellte and Hepste rise in south Powys on the southern slopes of Fforest Fawr. This headwater area is formed from Old Red Sandstone. Each then crosses a band of Carboniferous Limestone before traversing country formed by interlayered sandstones and shales traditionally referred to as the Millstone Grit. Within the limestone belt, short sections of each river flow underground, though that of the Hepste also flows at the surface during periods of particularly wet weather.

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