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
M62 motorway was constructed and allowances had to be made to counteract possible future subsidence. The motorway crosses the Irwell Valley and the Pendleton Fault on a single-span bridge above the river. Surveying for the Pennine section began in November 1961 and its route was determined in July 1963. Construction between Windy Hill and Pole Moor was difficult through inhospitable hilly terrain, peat bogs, and in undesirable weather conditions. The motorway's highest point, above sea level at Windy Hill near Saddleworth Moor () is the highest point of any motorway in England. A notable structure between junctions 21 and 22 on the