|Location Map ( geo)|
Bont Fawr in Dolgellau crosses the Afon Wnion and the line of the former Cambrian Coast Railway at the northern end of the town centre. For many years it carried the A470, however when the town was bypassed, by routing the road along the old rail line, the bridge became unclassified, with the northern section being rebuilt to cross the A470 instead!
Dating back to 1638 in part, the bridge almost certainly replaced an earlier crossing of the river in this historic town. The oldest sections still standing are the piers and spandrels, including at least part of the arches themselves. However, the bridge has been remodelled many times since, first in the early 19th Century which is where most of the arches date from. The northern two arches date from the addition of the span over the former railway in 1870, which required the gradient across the bridge to be increased to give the necessary clearance. The latest work was done when the bypass was constructed, and the old span over the railway removed to be replaced by a new concrete span. At the same time, the modern footbridge was added to the eastern flank of the old bridge.
The bridge is described as a 7-arch structure, although the southern 2 at the town end are hardly visible, as they are little more than low flood arches. The next 5 span the river when it is full, although when levels are low only the northern 4 spans actually cross water. Of these, the 2 northernmost are the new spans built in 1870. The cutwaters on the downstream side are more butresses than cutwaters, but on the upstream side two of the cutwaters are substantial structures, supporting the modern footway above. Whilst the stonework looks old, it is probably contemporary with the bypass.
The span across the bypass is a single concrete span which sits wider than the older part of the bridge, and incorporates the modern footway within its width. The bridge climbs across its length from the town end, with the parapets stepping up over the two 1870 arches, and then giving way to metal railings over the bypass. The roadway over the older parts of the bridge does include a narrow pavement on the west side.