The works on the line were always expected to be difficult, and progress was slow. In 1848 it was decided to open from Chester to Bangor. Captain Wynne of the Board of Trade visited for the required inspection for passenger opening, on 19 and 20 April 1848. He inspected the line as far as the Conway, his colleague Captain J L A Simmons inspected the line westward from there. The inspectors were informed that the line would be worked by the London and North Western Railway. (By Act of 16 July 1846 the London and Birmingham Railway, the Grand Junction Railway and the Manchester and Birmingham Railway merged to form the London and North Western Railway.)