The original viaduct across the Tawe valley, built in 1847-50, was one of Brunel's timber structures with some masonry piers. It was replaced in 1888-89 by a steel girder bridge and the eastern part converted into an embankment. The decking was renewed in 1978-79. The five masonry piers, each with two arched openings, which support the bridge where it crosses the river, belong to the original structure. The main span has a length of 30.5 metres (100 feet).

Source:
Stephen Hughes and Paul Reynolds (1989) 'A Guide to the Industrial Archaeology of the Swansea Region' Association for Industrial Archaeology.

RCAHMW, 19 October 2011.