Meldon viaduct's wrought and cast iron trestles carried their first train on 12th October 1874. Built by Engineer W R Galbraith for LSWR's Lydford-Okehampton line, the track sat 150 feet above the valley on a rising gradient of 1 in 77 towards the west, incorporating a 30 chain radius curve. Originally it was single track but, in 1878, was doubled by erecting a second viaduct on the south side, linked by extending the deck and bracing the tops of the trestles.