George Stephenson built the L&MR to the same gauge as the tramroads in use in the North Eastern colliery railways he had grown up working on: a rail gauge of , and all railways built by him and his assistants adhered to that gauge. When Bristol businessmen wished to build their railway linking their city with London, they chose Isambard Kingdom Brunel as their engineer. Brunel favoured a wider gauge of . He felt that the different railways would not be in close enough proximity to warrant adherence to a uniform British gauge. Thus, the Great Western Railway (GWR) (completed in 1841) was constructed to Brunel's 'broad' gauge. However, his assumption proved incorrect, and when railways of a different gauge met, the inconvenience led to an officiating organization looking into the matter. Their conclusion was that Stephenson's "narrow gauge" should be adopted as Britain's standard gauge, and Parliament passed the 1846 Gauge of Railways Act which stipulated the standard gauge of .