Craigellachie Bridge

Craigellachie Bridge is a cast iron arch bridge across the River Spey at Craigellachie, near to the village of Aberlour in Moray, Scotland. It was designed by the renowned civil engineer Thomas Telford and built from 1812 to 1814. It is a Category A listed structure.
The bridge has a single span of approximately 46 metres and was revolutionary for its time, in that it used an extremely slender arch which was not possible using traditional masonry construction. The ironwork was cast at the Plas Kynaston iron foundry at Cefn Mawr, near Ruabon in Denbighshire by William Hazledine, who cast a number of Telford bridges. The ironwork was transported from the foundry through the Ellesmere Canal and Pontcysyllte Aqueduct then by sea to Speymouth, where it was loaded onto wagons and taken to the site. Testing in the 1960s revealed that the cast-iron had an unusually high tensile strength. This was probably specified by Telford because, unlike in traditional masonry arch bridges, some sections of the arch are not in compression under loading.

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