River Usk (Afon Wysg)

The Usk reservoir, viewed from Carmarthenshire.

The s River Usk (Welsh: Afon Wysg) rises as a small stream on Waun Lwyd, some 500 metres up on the slopes of the Black Mountain. For approximately 5 kms it forms the county boundary of Carmarthenshire before entering the Usk reservoir, built in 1955 to supply water for Swansea.

Pont a'r Wsyg is a hotpotch of alterations and additions of no particular aesthetic or architectural value, apart perhaps for its location. It is however noteworthy for being the only road bridge across the Usk in Carmarthenshire.

There are also a couple of temporary bridges further north that now allow a mountain bike trail to wind its way around the whole reservoir.