 Barmouth Bridge ( Welsh : Pont <unk> ) , also known as Barmouth Viaduct , is a single @-@ track largely wooden railway viaduct that carries the Cambrian Coast Railway across the River Mawddach estuary on the coast of Cardigan Bay , Wales . It sits between Morfa Mawddach and Barmouth in Gwynedd and caters for rail , foot and cycle traffic . 
