Railway Bridge (171c) Grand Union Canal

This is a railway bridge built in 1834-5 for the London and Birmingham Railway, designed by Robert Stephenson. It carries the railway line over the Grand Union Canal at Wolverton. The bridge was likely widened in 1889 by the London and North Western Railway.

The structure comprises sixteen cast-iron I-beams supported on abutments constructed of red and blue engineering brick with a stone bearing. One beam is marked with relief lettering indicating it was manufactured by the Butterley Iron Company of Derby. The beams feature consistent concave-shaped bracing to the web, with some having double bracing and others single. One original beam incorporates moulded timber infill panels, and two later wrought iron or steel-riveted girders have been added to this side of the bridge. The bridge was originally constructed in two sections of eight beams each, with a central space later filled with steelwork to accommodate a single railway line providing access to the works. The original cast-iron plates remain in place for the decking. Modern timber boarding and steel railings now serve as parapets, replacing the original balustrades lost during the widening.

The London and Birmingham Railway, which later became part of the London and North Western Railway, built the bridge. The section of line passing through the company's engineering works was originally four-track wide, explaining the bridge’s substantial width. After 1882, passenger trains ceased to use the bridge and it was spared replacement, despite the widespread failures of other cast iron beam bridges at the time. As such, this bridge is now exceptionally rare, possibly unique on this scale, and represents the original structure described by John Britton in 1838.