The Balerno line was a short loop railway in Scotland. It was some 6 miles in length leaving the main Caledonian Edinburgh to Carstairs line at Slateford in Edinburgh. It was built by the Caledonian Railway (CR) mainly to service the many enterprises situated along the upper Water of Leith. However, passenger trains also ran. Most trains terminated at Balerno, though they had to travel to Ravelrig to turn round. Other stations were constructed at Colinton, Juniper Green and Currie. In 1923, with the grouping, the CR amalgamated with several other companies to form the London, Midland and Scottish Railway (LMS) which, following nationalisation in 1947, became part of British Railways.