The South Devon and Tavistock Railway linked Plymouth with Tavistock in Devon; it opened in 1859. It was extended by the Launceston and South Devon Railway to Launceston, in Cornwall in 1865. It was a broad gauge line but from 1876 also carried the standard gauge (then referred to as narrow gauge) trains of the London and South Western Railway between Lydford and Plymouth: a third rail was provided, making a mixed gauge. In 1892 the whole line was converted to standard gauge only.
The line closed to passengers in 1962 although sections at either end were retained for a while to carry freight traffic. A short section has since been reopened as a preserved line by the Plym Valley Railway.
History
Getting the Tavistock line authorised
The Plymouth and Dartmoor Railway, a horse-worked line, had been constructed to bring minerals from quarries near Princetown to Plymouth; it opened on 26 September 1823.
The South Devon Railway (SDR) built its line from Exeter to Plymouth, opening to a temporary station at Laira Green on 5 May 1848. It extended to its Plymouth terminus at Millbay on 2 April 1849 for passengers, with goods traffic starting on 1 May 1849. Continuous rail transport from Plymouth to London was now possible.
Promoters in the important towns near the Devon–Cornwall border developed schemes to connect their region to the new railway main line, including an early Launceston and South Devon Railway, but that proposal expired in 1846; there were also competing schemes, including a Plymouth, Tavistock, Okehampton, North Devon and Exeter Railway for a line connecting with the London and South Western Railway.
It was the South Devon and Tavistock Railway which obtained its Act of Parliament on 24 July 1854, authorising construction of a line from Tavistock to a junction with the South Devon Railway east of Plymouth; the track gauge was to be the broad gauge, , and authorised capital was £160,000 with borrowing powers of £53,600.
As well as serving the connected communities, the line had the strategic purpose of blocking incursion by competing narrow gauge companies, sponsored by the London and South Western Railway (LSWR). However, in the final stage of getting the Bill passed, it was in the Lords Committee stage. Anthony says
There was period of anxiety in May, when it was rumoured that the House of Lords would compel the Company to introduce a clause for the narrow gauge to be adopted over the whole of the line, and even to carry it into Plymouth.
The Lords did not, in fact, insist on the narrow gauge being laid throughout, but at the last moment, when the Bill came before Lord Reedsdale, he, without receiving any evidence upon the subject, and "by the immense authority he possessed in such matters", forced into the Bill a clause, that should a narrow gauge line ever connect itself with the Tavistock branch the Company would be obliged to admit the narrow gauge upon their system.
Construction
The Crimean War was in progress at the time, and the start of construction was delayed until September 1856. The chief engineer, A. H. Bampton, died a few months after the start of work, and the services of Isambard Kingdom Brunel were called in. The works were heavy, with three tunnels and six timber viaducts on stone piers.
The line was opened to passenger traffic on 22 June 1859, and for goods on 1 February 1860; it was worked by the South Devon Railway (SDR); trains from Tavistock joined the SDR main line at Tavistock Junction and ran to their Plymouth terminus at Millbay, a distance of 3½ miles.
Extension to Launceston
On 30 June 1862 the independent Launceston and South Devon Railway gained its Act of Parliament to extend the broad gauge line from Tavistock on to Launceston. In contrast to the South Devon and Tavistock line, there were no engineering works of any difficulty, and the line opened to passengers on 1 June 1865, and for goods in October 1865. The Launceston line too was worked by the SDR from the outset.
On 1 July 1865, the Tavistock and South Devon Railway merged with the South Devon Railway (SDR), and the Launceston company was later absorbed under an Act of Parliament on 24 June 1869. The South Devon Railway, in turn, amalgamated with the Great Western Railway (GWR) and the Bristol and Exeter Railway on 1 February 1876. The combined company was called the Great Western Railway.