Looking over the right-hand parapet wall of the bridge, you can see the sandstone chasm which carries the Liverpool & Manchester Railway towards Broad Green and beyond. Cross Mill Lane, with care, and look over the other parapet of the bridge towards the city centre. In 1830, when the line opened as the world's first passenger railway, the cutting must have looked even more spectacular, for it was only half the present width. George Stephenson, the railway's engineer, had hoped to avoid such problems by routeing the line further north. However, objections from the Earls of Derby and Sefton forced him to adopt this approach to Liverpool, through a cutting nearly two miles long and up to 70 feet deep. The work was carried out by an army of navvies, with the help of horses and explosives but very few mechanical aids. On its completion, the cutting was regarded as one of the wonders of the age, and people from Liverpool and elsewhere would travel to the Mill Lane bridge to gaze down upon the 'Rocket' and its fellow locomotives.

The growth of rail traffic was such that, before long, the cutting was increased in width from two to four tracks. Some of the extracted stone was made available for local building work, rather than simply being used to enlarge the Roby embankment. In the middle distance - in front of the Roman Catholic cathedral's distinctive silhouette - are the buildings and landscaping of the Wavertree Technology Park, which was created from 1983 onwards on the site of another 'wonder of the railways': the Edge Hill Gridirons.