Castell Malgwyn Bridge was built by Sir Benjamin Hammet in 1799 to carry the Llechryd-Boncarth road over a newly built (1772) canal (NPRN: 404580) which supplied power to the Castell Malgwyn Tinplate Works (NPRN: 404326). It is a shallow-arched rubble stone bridge with a cut stone arch. On either side are cast iron keystones with Sir Benjamin's crest (castle and crossed cannons motif), with on the east side 'Castle Malgwyn Bridge 1799' and on the west 'Sir Benjn Hammet 1799'

See the article by Leslie Leigh on 'Pont ar Ddyfi' in the Journal of the Merioneth Historical and record Society, vol. XIV: 4 (2005), pp. 319-26.
R.F.Suggett, RCAHMW, December 2005.

Louise Barker, RCAHMW 8th March 2006