The Border Union Railway was a railway line which connected places in the south of Scotland and Cumberland in England. It was authorised on 21 July 1859 and advertised as the Waverley Route by the promoters - the North British Railway. It connected the Edinburgh and Hawick Railway at Hawick with Carlisle.
The first section of the route was opened between Carlisle and Scotch Dyke on 12 October 1861, to Newcastleton on 1 March 1862, Riccarton Junction on 2 June 1862 and throughout on 24 June 1862. The railway was built as a double-track main line throughout.
The line was closed to all traffic by British Railways on 5 January 1969. The line was dismantled in 1971.
The Waverley Route Heritage Association have preserved a part of the former route at Whitrope and are working on reopening the section from its base at Whitrope itself down into Riccarton Junction as a heritage railway.