The 18th century Iron Bridge spanning the River Severn at Coalbrookedale in Shropshire, England. It was the first cast iron bridge in the world to be built & has come to be regarded as a symbol of the beginning of the Industrial Revolution. Iron Bridge is also one of the last of its type to have survived intact. More than one person was involved in the design of the bridge, although Thomas Farnolls Pritchard appears to have played the major role. It was built by Abraham Darby 111 & completed in 1779. The weight of iron in the bridge is approximately 385,082 kilograms (379 tons).