Caledonian Main Line

The Caledonian Main Line represents most of the original route of the Caledonian Railway: a major Scottish railway company. The company was formed in 1830 and was absorbed almost a century later into the London, Midland and Scottish Railway, in the 1923 railway grouping, by means of the Railways Act 1921. When first opened, the Caledonian Main Line represented the only railway link between England and Scotland: running from Carlisle to Carstairs; and then to both Edinburgh and Glasgow. The Edinburgh terminus was at Princes Street; and the original Glasgow terminus at Buchanan Street, the latter being reached by use the Garnkirk and Glasgow Railway's metals. The Caledonian railway's Glasgow terminus was later moved to Glasgow Central and was accessed via the Clydesdale Junction Railway. A short section between Carlisle and Gretna was used to give the Glasgow and South Western Railway access to Carlisle and the North British Railway's Waverley Line.

Princes Street has closed, as has the Waverley Line, but Caledonian Main line together with the former Clydesdale Junction Railway are still in use today as the northern section of the West Coast Main Line, between Carlisle, Glasgow Central and Edinburgh Waverley stations. The link at Gretna remains open, as part of the Glasgow South Western route.