M18 motorway (Great Britain) and 12 June 2015. The M18 was originally to be part of the M1, but it was decided to route the M1 towards Leeds instead of Doncaster, and the routing of what would have been the M1 east of Sheffield became the M18. Data from driver location signs are used to provide distance and carriageway identifier information. The location sequence is a continuation of the M1 location sequence. !scope=col|miles !scope=col|km !scope=col abbr="Southbound"|Southbound exits (B carriageway) !scope=col|Junction !scope=col abbr="Northbound"|Northbound exits (A carriageway) !scope=col|Coordinates M18 motorway (Great Britain) The M18 is a motorway in Yorkshire, England. It runs from the east of
M1 motorway carried by bridge but no longer reaches the northbound carriageway as it is cut off by the motorway continuing south. The final section of the M1 was opened to Junction 1 at Staples Corner in 1977. There the motorway meets the North Circular Road (A406) at a grade separated junction and roundabout. Unrealised plans made in the 1960s would have seen the motorway continue through the junction on an elevated roadway to end at West Hampstead where it would have met the North Cross Route, the northern section of the London Motorway Box, a proposed ring of urban motorway around