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The Landore railway viaduct crosses the Swansea valley and the River Tawe at Landore in South Wales. It provides a link between Swansea city centre and the West Wales Line to the South Wales Main Line.
The original viaduct was designed for the South Wales Railway by Isambard Kingdom Brunel. Construction started in September 1850and was complated in June 1850. The contractor was George Hennet of Bristol. 
The viaduct had a total of 40 spans and was 1/3 mile (563m) long. The longest span,of 102 ft over the navigable channel of the river, was a composite structure of timber and wrought iron.
Assessment by William George Owen in 1880 showed the viaduct to be in good condition, but by 1882 he recommended gradual reconstruction, using masonry piers and iron girders. The work was completed in 1888.
In 1978/9 steel girders replaced the iron ones.
For more information, see 'Brunel's Timber Bridges and Viaducts' by Brian Lewis