It runs south west from Edinburgh for approximately 70 miles, through Saughton, Wilkieston and south of Livingston, Whitburn and Wishaw, then by way of Overtown, Garrion Bridge, Stonehouse, Strathaven, Darvel, Newmilns, Galston, Hurlford and Kilmarnock to Irvine on the North Ayrshire coast.