One of the greatest feats in the history of British engineering is undoubtedly the iconic Iron Bridge. It’s one of Britain’s best known industrial monuments, and a world heritage site. Located in the county of Shropshire, The Iron Bridge crosses the river Severn and was the first arch bridge in the world to be constructed using cast iron. As such, the bridge was seriously celebrated at the time of its opening in 1781.
Interestingly, during the 18th century, this part of Shropshire became a centre for industry, and was an industrial power-house thanks to its rich coal deposits, and the River Severn was a major trading route. However, those wishing to traverse its banks were faced with a major physical barrier, namely The Severn Gorge.
The impracticality of crossing this section of the river was, in many respects, hindering the expansion of industrial activity in the area, thereby necessitating the building of a bridge. However, engineers faced a number of challenges with regards to the proposed construction of this new bridge. Not only did they have the instability and steepness of the river’s bank to contend with, the bridge would also have to be high enough to allow the many tall ships frequenting the river to safely pass underneath.
The proposal for the design of the bridge came from the architect Thomas Farnolls Pritchard in 1773, who also put forward the idea that the bridge should be made from cast iron. However, it was to be a few years later, in 1776, before the plans finally received royal assent. An iron master by the name of Abraham Darby III was commissioned to cast and build the bridge, which was finally completed in 1779. A total of 378 tons of iron was used in its construction.
In recent years further information has come to light regarding how the bridge was actually built. Thanks to the discovery, in 1997, of a watercolour sketch of the bridge during the period of its construction, we now know that a large majority of the bridge’s components, including the large castings, were made individually to fit, and consequently each is slightly different from the rest. The bridge consists of five main cast iron ribs, each with a span of 30.6 meters.
The bridge was finally opened to the public on New Year’s Day in 1781, and was used extensively proving to be of great commercial importance for the local area up until its closure in 1934 , following its designation as an Ancient Monument.
During its long history, the bridge has been repaired on a number of occasions. For example, in July of 1983, an additional wall was built in order to prevent parts of the bank from slipping into the river. Engineers have also undertaken a project to restore the bridge, with a number of repairs being carried out between 1972 and 1975.
The Iron Bridge is one of numerous examples of the long and rich tradition of great British engineering. Here at Airedale springs we’re high quality spring manufacturers and proud to be a part of this continuing tradition. For more information about our range of products and services please don’t hesitate to contact us and a member of our friendly team will be happy to help you with your enquiries.