Many of the structures of the Weaver navigation are of historical importance, and are grade II listed. They include the Hayhurst swing bridge and Northwich Town bridge, which are believed to be the earliest swing bridges powered by electricity. Both have a sectional pontoon, which is immersed in the river and carries about 80 per cent of the weight of the bridge. Dutton Horse Bridge, which carries the towpath over the weir stream at Dutton, is one of the earliest surviving laminated timber structures. Dutton railway viaduct, which was built by Joseph Locke and George Stephenson for the Grand Junction Railway, is grade II* listed, and a civic celebration was held on its completion, as there had been no deaths and no serious injuries to the workers during its construction.