Which English bridge became the world’s first iron bridge when it opened in 1781?

The Iron Bridge became the world’s first iron bridge when it opened in 1781.

It crosses the River Severn at Ironbridge Gorge in Shropshire, England. Abraham Darby III oversaw its construction, while architect Thomas Farnolls Pritchard had proposed the design. The bridge used cast iron supplied by the nearby Coalbrookdale ironworks, making the material itself a major part of its historical importance.

The bridge was assembled from large cast-iron pieces using methods related to timber bridge construction. Its arch spans 30 metres, and the structure demonstrated that iron could be used for a substantial crossing rather than only for small components. The name “Ironbridge” also refers to the nearby town and the gorge, so the bridge should not be confused with a generic iron viaduct. It became a UNESCO World Heritage Site in 1986.