The Cumberland Gap is the term used for what between 1999 and 2008 was the last non-motorway stretch of the 400-mile route from London to Glasgow. It comprised 5.7 miles of A74 that remained between the north end of the M6 and the south end of the A74(M).
It ran from Greymoorhill or Kingstown Interchange on the M6, just north of Carlisle, to Guardsmill Interchange on the A74(M) just south of the Anglo-Scottish border near Gretna.
Between July 2006 and December 2008, the Cumberland Gap was upgraded to become part of the M6. It was opened on December 5 2008, the 50th anniversary of the opening of the first section of M6, the Preston Bypass.