sea before being recaptured and finally pushed back into place. The tubes were manoeuvred into place between June 1849 and February 1850. Once in place, the separate lengths of tube were joined to form parallel prestressed continuous structures, each one possessing a length of and weighing . The pre-stressing process had increased the structure's loadbearing capacity and reduced deflection. The tubes had a width of and differed between and in overall depth, while also having a gap between them; they were supported on a series of cast iron beams that were embedded in the stonework of the towers. To better protect the iron from the weather, an arched timber roof was constructed to cover both tubes; it was roughly wide, continuous over their whole length, and covered with tarred hessian. A wide central walkway was present above the roof for the purpose of producing maintenance access. On 5 March 1850, Stephenson himself fitted the last rivet of the structure, marking the bridge's official completion. Altogether, the bridge had taken over three years to complete. On 18 March 1850, a single tube was opened to rail traffic. By 21 October of that year, both tubes had been opened to traffic. For its time, the Britannia Bridge was a structure of "magnitude and singular novelty", far surpassing in length both contemporary cast beam or plate girder iron bridges. The noted engineer Isambard Kingdom Brunel, a professional rival and personal friend of Stephenson's, was claimed to have remarked to him: "If your bridge succeeds, then mine have all been magnificent failures". On 20 June 1849, Brunel and Stephenson had both looked on as the first of the bridge's tubes was floated out on its pontoons. The construction techniques employed on the Britannia Bridge had obviously influenced Brunel as he later made use of the same method of floating bridge sections during the construction of the Royal Albert Bridge across the River Tamar at Saltash. There was originally a railway station located on the east side of the bridge at the entrance to the tunnel, run by the Chester and Holyhead Railway company, which served local rail traffic in both directions. However, this station was closed after only years in operation owing to low passenger volumes. In the present day, little remains of this station, other than the remnants of the lower-level station building. A new station named Menai Bridge was opened shortly afterwards.