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
M12 motorway M12 motorway The M12 is a length of spur motorway in County Armagh, Northern Ireland. It was opened in 1970. It leads off the main M1 motorway, to Portadown, part of the conurbation of Portadown-Craigavon-Lurgan, and forms most of the route between junction 11 of the M1 (Ballynacor) and the A3 Northway at Kernan Loop. The road forms part of European route E18. The M12 is a legacy from the 1960s plan to develop the Craigavon new town. The M1 motorway was originally intended to run between Belfast, and the area that is now Craigavon. By the early 1960s, the