Now we are back on the path and walking down to the base of the bridge and I should explain to you why I said that 'originally, the only people who used this bridge crossed by means of the railway'. Well this isn't the bridge that Stephenson built, the supports are the same but not the spanning steelworks. What happened was this - back in 1970 some boys were exploring the entrance to the tunnel which carried the railway, couldn't see much so put a match to some paper which was lying about, they dropped the paper and a fire started. Unfortunately the roof of the tunnel consisted of tar-coated wood resulting in an inferno which could not be controlled. Because of the importance of the bridge (the mainline from London to Holyhead) it was rebuilt with a single track in just less than two years. The top deck which carries the A55 was added eight years later.