Yodo Line

The line began as a 762 mm gauge light railway built by the private Uwajima Railway (宇和島鉄道). The project grew out of an earlier, unrealised railway scheme around Uwajima; after Iyo Railway's Inoue Kaname encouraged a fresh attempt, promoters applied for a line and a provisional licence was granted in 1896, with a full licence in 1897. An initial company was wound up in 1905, and the venture was re-established before construction finally went ahead. On 18 October 1914 the Uwajima Railway opened its first section, between Uwajima and Chikanaga, worked by steam. The line was extended from Chikanaga to Yoshino (now Yoshinobu) on 12 December 1923, and in 1931 the company introduced a single gasoline railcar.

The Uwajima Railway was nationalised on 1 August 1933, becoming the Uwajima Line (宇和島線). At that point it ran only from Uwajima to Yoshinobu and was an isolated line with no connection to the rest of the national network; several stations were renamed, including Miyanoshita to Iyo-Miyanoshita and Nakano to Futana. In 1941 the Uwajima–Unomachi section that would become part of the Yosan Line opened, and in conjunction the line was re-gauged to the national 1,067 mm standard on 2 July; the old Uwajima–Takagushi alignment was abandoned, a new Kita-Uwajima–Muden route opened, and Kita-Uwajima became the line's starting point. On 20 June 1945 the Uwajima–Kita-Uwajima–Unomachi stretch was separated off as part of the Yosan Main Line.

After the Second World War the line was extended in two stages with the goal of linking Ehime (Iyo) and Kōchi (Tosa). The Yoshinobu–Ekawasaki section opened on 26 March 1953. The final gap, the Ekawasaki–Wakai section, was built by the Japan Railway Construction Public Corporation under the construction name "Kuboe Line" (窪江線) and opened on 1 March 1974, completing the through route and connecting it to the Dosan Line at the Kubokawa end. On full opening the whole line was renamed the Yodo Line, taking the leading characters of the two old province names. CTC signalling was commissioned that September, and freight operations ended on 1 October 1974.

The line has weathered both natural disasters and the threat of closure. In 1976 an embankment collapse and a rockfall on a bridge cut services, and the entire line was replaced by buses for a period before through running resumed on 24 September. When the 1980 JNR Reconstruction Act set up a process for abolishing unprofitable local lines, the Yodo Line's traffic fell below the survival threshold, but it was kept open because the parallel roads were not yet adequately developed; the nine municipalities along the route had formed a preservation league to defend it. On 1 April 1987 the line passed to JR Shikoku in the privatisation of Japanese National Railways, and one-man (wanman) operation began on 10 April 1988. The nickname "Shimanto Green Line" came into use on 27 July 1997.

With ridership low — among the weakest on JR Shikoku's network — the line has leaned heavily on tourism to draw passengers, and it is best known today for a family of novelty trains. The oldest is the Shimanto open-car "Torokko" train, which began in 1984 as Japanese National Railways' first torokko train from a converted freight wagon and which, after a 2013 redesign by Eiji Mitooka, runs as the yellow "Shimanto Torokko." From July 2011 the Kaiyodo Hobby Train, created with the figure manufacturer Kaiyodo, has displayed model figures aboard, and from 15 March 2014 the Tetsudo Hobby Train, styled after a first-generation 0 Series Shinkansen and fitted with seats from a scrapped 0 Series, has run on the line. In February 2014 the three were grouped together as the "Yodo Line Three Brothers" (予土線3兄弟).

The Yodo Line remains a quiet, slow-paced local railway whose appeal lies in its scenery and its trains rather than in fast or frequent service. Its modern timetable has thinned — the Ekawasaki–Kubokawa section was cut to five round trips in 2020 and four in 2021 — and the corridor was suspended entirely after flooding in the heavy rains of July 2018, reopening on 10 August that year. Concerned about the line's future, the prefectural-side promotion councils for Ehime and Kōchi merged into a single Yodo Line Promotion Council in 2023 to coordinate efforts to keep the line running.

• 1896January: a provisional licence is granted to the Uwajima Railway for a line between Uwajima and Yoshinomura.
• 189721 April: the full railway licence is granted; the Uwajima Railway company is established that April.
• 191418 October: the Uwajima Railway opens its first section, Uwajima–Chikanaga (762 mm gauge), worked by steam.
• 192312 December: the line is extended from Chikanaga to Yoshino (the present Yoshinobu).
• 19331 August: the Uwajima Railway is nationalised by Japanese Government Railways, becoming the Uwajima Line; several stations are renamed.
• 19412 July: the whole line is re-gauged to 1,067 mm; the old Uwajima–Takagushi alignment is abandoned, a new Kita-Uwajima–Muden route opens, and Kita-Uwajima becomes the line's starting point.
• 194520 June: the Uwajima–Kita-Uwajima–Unomachi section is split off as part of the Yosan Main Line.
• 195326 March: the Yoshinobu–Ekawasaki section opens.
• 19741 March: the Ekawasaki–Wakai section opens, completing the through route and connecting to the Dosan Line; the line is renamed the Yodo Line. CTC signalling is commissioned in September and freight operations end on 1 October.
• 1976An embankment collapse and a rockfall on a bridge cut services; the line is replaced by buses for a period before through running resumes on 24 September.
• 1981March: under the JNR Reconstruction Act, the line is excluded from the list of lines to be abolished because its parallel roads are not yet adequately developed, despite traffic below the survival threshold.
• 19871 April: the line passes to JR Shikoku in the privatisation of Japanese National Railways.
• 198810 April: one-man (wanman) operation begins.
• 199727 July: the nickname "Shimanto Green Line" comes into use.
• 201415 March: the Tetsudo Hobby Train, styled after a 0 Series Shinkansen, enters service; in February the Shimanto Torokko, Kaiyodo Hobby Train and Tetsudo Hobby Train are grouped as the 'Yodo Line Three Brothers'.
• 20188 July: flooding in the heavy rains of July 2018 suspends the entire line; service resumes on 10 August.