Iron Bridge

The Iron Bridge in the eponymous town of Ironbridge – today one of the southern suburbs of Telford – is one of the historically most important bridges in the UK, if not the world. It was the first bridge ever to be constructed solely from iron (with the obvious exception of the deck). Construction of the bridge started in 1779, and the bridge opened in 1781.

In the original road numbering scheme of 1922, it was made part of the B4377. It was closed to vehicular traffic in 1934, but despite that closure, it was still officially a classified road, becoming part of the B4373 in the 1935 Road numbering revision, before finally becoming unclassified in the 1960s.

The Iron Bridge is now a World Heritage Site.

Planning

The River Severn in the area featured many small ferries, though their reliability was very poor due to changing levels in the river. In order to solve the problem, Thomas Pritchard, a local Shropshire architect started designing a bridge constructed using iron in 1773, and persuaded John "Iron-Mad" Wilkinson, a famous industrialist to support the construction of the Bridge. Pritchard died soon after construction started, so never saw his bridge completed.

Wilkinson pushed through the relevant parliamentary bills to allow for construction to take place, and then raised the funds to construct the bridge, estimated at around £3,200.

Abraham Darby III, grandson of Abraham Darby (who devised new ways of smelting Iron Ore with Coke rather than the charcoal used before, allowing the Industrial Revolution to proceed) who owned the ironworks along the river, was commissioned to cast the bridge. He agreed to the commission much as a showpiece of what his company could do as a means to cross the river, and offered to cover any cost over-runs. The bridge ended up costing around £6,000 to build, leaving Darby with huge debts.

The Bridge

The Iron Bridge in its new shade of red

Built in 1779, the Iron Bridge is a testament to the skill and ingenuity of Thomas Pritchard. As he was venturing into the unknown, he looked at how bridges had been built in the past, and decided that he would build a bridge as if it was made of timber. Therefore, all of the members were cast individually and joined together in much the same way that timber bridges had been built for centuries. The obvious difference was that it was made of Iron instead. On the southern shore, the bridge is connected to the road by a further 2 spans, made from Iron, across the riverside lane, while on the north shore a more traditional Stone arch is used to cross the path.

After completion, the bridge became a major attraction in an otherwise black and unpleasant industrial landscape. Inevitably, the idea was copied and by the end of the century, the bridge had become the first of many. Most of those early copies have been replaced in the intervening 200 years, whether through reaching the end of their life, or because they weren't up to the modern traffic flow. Perhaps the original Iron Bridge has survived only because the traffic flow today is no more than it was when built, albeit with a far greater bias to people than horses!

Today, the bridge is pedestrianised and free to cross, but a major part of the Ironbridge Gorge Museums that operate several former industrial sites in the area as tourist destinations.

For most of its life, the bridge seems to have been painted a dark blue-grey colour (often appearing to be a weathered black in photos). However, when a full-scale restoration was commenced in 2017, it was discovered that the bridge was originally a reddish colour, not dissimilar to the colour of modern red-oxide paint. As a result, when the restoration was completed in 2018, the bridge was revealed in what is believed to have been its original colour scheme, which looks very strange when you see it for the first time!

Links

• English Heritage
• Ironbridge Gorge Museums
• BBC History Virtual Tour