The Railway line was opened by the South Devon & Tavistock Railway on June 22nd 1859, and ran from Plymouth (Tavistock Junction) to Tavistock.  On 1st June 1865 the line was extended to Launceston, via Lydford, by the Launceston & South Devon Railway.  Both these companies were subsidiaries of the South Devon Company Incorporated, who had operated the lines from the beginning.  They were amalgamated into the South Devon Company on 31st December 1873.