Longford Railway Bridge, Railway bridge in Longford, Tasmania.

Longford Railway Bridge is a wrought-iron lattice-truss bridge over the South Esk River, built in 1870 for the Launceston–Deloraine line. Its two continuous spans each measure 200 feet (61 m), with a 19-foot gap between the upper and lower chords. The girders were fabricated at the Gwaun-tre-Oda Works in Cardiff, Wales, and shipped to Tasmania.

Designed by the Irish-born engineer W.T. Doyne, the wrought-iron bridge was fabricated at the Gwaun-tre-Oda Works in Cardiff, Wales, shipped to Australia and opened in 1870 on the Launceston to Deloraine line, after load testing in mid-April. It cost AU£28,000. Its two 200-foot lattice truss spans were the equal longest in an Australian bridge until 1880, and it was listed on the now-defunct Register of the National Estate in 1978.

The bridge's four cast-iron fluted columns with ornamental capitals and the central ornamental casting are the only decoration the engineers allowed, as reported in The Cornwall Chronicle in April 1870. The structure was erected under contract by C. de Bergue to designs by Doyne, Major and Willett, and its rivet holes were drilled rather than punched.

The bridge carries the Western Railway Line over the South Esk River at Longford, on the Launceston to Deloraine route. Its deck sits 2 ft 6 in (76 cm) above the highest recorded flood level, and the abutments and centre pier are founded about 27 ft (8.2 m) below the river level. The structure is a working freight bridge, so view it from the riverbank rather than the track.

The rivet holes were drilled rather than punched, so none needed alteration even where several plates were bolted together; the rivets were fitted cold and driven at red heat. The girders rest on a cast-iron plate 7 feet in diameter with grooved ribs holding a steel pin, W.T. Doyne's device for expansion and contraction.