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Scarborough Bridge carries the railway line to Scarborough over the River Ouse in York, England. The first bridge was built in 1845, and has been renovated and rebuilt at least twice since its initial opening. A new bridge was installed in 2015 at a cost of £6 million. The first bridge had a pedestrian walkway which was loacted between the two running lines, this was later moved to the east side of the bridge (in the 1877 rebuild), and in the 2010s rebuild, the walkway became a separate wider bridge.

History
The foundation stone of the bridge was laid on 28 March 1845, and the bridge was opened to traffic on 7 July 1845 (at the same time as the rest of the line). The bridge was located much nearer to the city centre than was originally intended; the residents of Clifton objected to the line going through their suburb, and so even though the line had been originally meant to access the railway station from the north, (joining onto the line going to Darlington) it went straight into what is now the main station area. The first (1845) bridge, was built within five weeks without the aid of a cofferdam for the central pier; the water level of the river was lowered by reducing the amount held back by the Naburn Lock further downstream on the Ouse. The pier was supported on 28 cast-iron piles which were driven 24 ft down into the bed of the river. The main structure consisted of two 75 ft long cast-iron girders, (the width of the river being 148 ft at the bridging point, though both ends had a small viaduct section) and cost £3,918.

Besides carrying the railway tracks for the York to Scarborough line, the bridge also has a smaller pedestrian section on the eastern side (facing into the city). The original pedestrian walkway on the bridge of the 1845 structure was between the two running tracks, accessed through the stone archways, but this was moved to the eastern side in 1874, when the bridge as rebuilt with girders between the stone piers. The gap in the archways is 7 ft wide, and had a staircase inside in which pedestrians could access the path on the deck of the bridge. The 1845 bridge was 32 ft wide with timber guard rails on the bridge deck for the trains, and small fences guarding the walkway from the running lines. The bridge was later re-inforced with timber struts along its length, as a bridge of similar design collapsed in Chester. As a result of the main station in York being re-sited in 1877, the bridge is now only 40 m east of the platforms of York station.

By the 21st century, it was recognised that the ironwork was corroded, and that timbers within the structure were rotten. The bridge was subject to regular inspections, and though the rail traffic across the bridge was light, due to issues with the load upon it, engineers needed to be present whenever the bridge was used by visiting steam trains.

The bridge was replaced in 2015, with four new spans, each weighing 65 tonne built by Mabey of Chepstow and costing £6 million. In 2019, the footbridge on the eastern side was also replaced with a wider structure that was accessible for people on bikes and those with prams. Estimates show that the bridge is used by 3,000 people per day, but access to the footbridge was restricted when the river was in flood; the new structure would be accessible when the Ouse was flooded. Usage surveys carried out on the bridge after it opened in 2019, show that footfall across the bridge had increased to 4,000 people per day. The unused stairways in the bridge ends were treated with a structural resin which completely fills all the holes and gaps in the void of the stonework. Due to the difficult nature of installing the new bridge with a crane, the nearby Marygate car park was closed off and one of the engineers built a model of the project in Lego to explain the complexity of the project to other workers involved in reconstructing the bridge.