The Silver Jubilee Bridge (originally the Runcorn–Widnes Bridge or informally the Runcorn Bridge) crosses the River Mersey and the Manchester Ship Canal at Runcorn Gap between Runcorn and Widnes in Halton, England. It is a through arch bridge with a main arch span of 361 yards (330 m). It was opened in 1961 as a replacement for the Widnes-Runcorn Transporter Bridge. In 1975–77 the carriageway was widened, after which the bridge was given its official name in honour of the Queen's Silver Jubilee. It carries the A533 road and a cantilevered footway. The bridge is recorded in the National Heritage List for England as a designated Grade II listed building. The bridge was closed to vehicles for refurbishment upon the opening of the new Mersey Gateway Bridge, but reopened as a toll bridge in February 2021. History Before construction Until 1868, when Runcorn Railway Bridge was opened, the only means of crossing the Mersey at or near Runcorn Gap were by fording or by ferry, with the lowest crossing of the river being the road bridge at Warrington. The first bridge to carry vehicular traffic across Runcorn Gap was the Widnes-Runcorn Transporter Bridge which opened in 1905. This was an inefficient means of transport and it had become inadequate for the amount of traffic using it before the outbreak of World War II. In 1946 the Ministry of Transport agreed that the transporter bridge should be replaced when sufficient funds were available. Mott, Hay and Anderson were appointed as consultant engineers. Planning The new bridge had to allow the passage of shipping along the Manchester Ship Canal. Many ideas were considered, including a new transporter bridge or a swing bridge. These were considered to be impractical and it was decided that the best solution was a high-level bridge upstream from the railway bridge. This would allow the least obstruction to shipping and would also be at the narrowest crossing point. The first plan for a high-level bridge was a truss bridge with three or five spans, giving an dual carriageway with a cycle track and footpaths. This was abandoned because it was too expensive, and because one of the piers would be too close to the wall of the ship canal. The next idea was for a suspension bridge with a span of between the main towers with an single carriageway and a footpath. However aerodynamic tests on models of