The Iron Bridge across England's longest river,the severn,is the world first iron bridge.At one time,the surrounding area was a remarkable concentration of industrial activity.Today the area under the bridge and on both sides known as the Ironbridge Gorge,is a world heritage site,in recognition of its outstanding importance in the early development of industrialisation.The Iron Bridge was built in 1779 and was opened on New Year's day in 1781.It is a testimony of the first large-scale use of iron for structural purposes in the world and a remarkable demonstration of the utility and versatility of iron for construction.With a span of 30 metres,the graceful semi-circular arch reached across the gorge of the Severn at its narrowest point.The Iron Bridge was not only a singular example of new engineering but also a tremendous success.Its symbolic significance was great,not only in Britain but throughout Europe and the United States.
Proper international fame and recognition came with the designation of the Gorge and the bridge as a world Heritage Site in 1986.It is the first industrial area to be listed as a World Heritage Site.