SH6640 : Bridge at Maentwrog, Gwynedd SH6640 : The old Pont Maentwrog bridge"Pont Maentwrog has three elliptical arches with triple keystones, each part consisting of three thin stones. This feature also appears in Pont Rhyd Lanfair over the Conwy, which was built in 1780, and it is probable that Pont Maentwrog was built about the same date."
Edward Jervoise,
Ancient bridges of Wales (London, 1936), p.52
Gwyndaf Breese also remarks on the similarity in style to Pont-Llan at Penmachno, built in 1785.