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River in Powys, Wales
Dulas is a left-bank tributary of the Afon Irfon, itself a tributary of the River Wye. It rises on the southeastern slopes of the Elenydd and runs southeast to join the Irfon at Garth. The river is bridged by both the B4358 and the A483 roads.
References
Ordnance Survey 1:50,000 scale Landranger map sheet 147 Elan Valley & Builth Wells area