Afon Llia

Afon Llia is a short river in Powys, Wales, and which is wholly contained within the Brecon Beacons National Park. Several streams draining the eastern slopes of Fan Nedd and the western slopes of Fan Dringarth in the Fforest Fawr section of the national park meet to form the river, which then flows southwards for 5 kilometres (3.1 mi) to its confluence with Afon Dringarth, the combined waters continuing south as Afon Mellte. The name probably derives from the Welsh root lly– found in llyfu, llyo ('lick, lap') but it has probably been influenced by the local pronunciation of lleiaf ('smallest'). The river flows over ground formed from Old Red Sandstone rocks laid down during the Devonian period. The valley was inundated by ice during the last glacial period as evidenced by the low mounds of moraine present in the valley and through which the river has since cut.

Flows through: United Kingdom.

River data from Wikidata (CC0); lengths normalised to a common unit.