This is a Viaduct which was completed in 1878. The architect and builder was Owen Gethin Jones who was born in 1816 at Penmachno and was educated at the school there. He was brought up as a stone mason and a carpenter. He first built a factory which turned out a success. He entered into partnership with two relatives and commenced railway work. The partnership made a line from Penmachno to Ffestiniog, on the London and North Western from Bangor to Rhyl and Mostyn and from Betws to Dolwyddelan.
In Dolwyddelan, Gethin's Bridge is a large, strong bridge with thirty-eight arches. The viaduct is over a deep gorge. The partnership also built the school and vicarage at Penmachno, Brynderwen Mansion at Llanrwst and other structures.
Owen Gethin Jones died in 1883, aged 66.
Original Index No. X0055.