Geibi Line

The line was assembled over two decades from three separately built railways. The oldest section was the work of a private company, the Geibi Railway, whose first segment — Higashi-Hiroshima Station (a first-generation station unrelated to the present Higashi-Hiroshima Station) to Shiwachi — opened on 28 April 1915, with an extension to Miyoshi (the present Nishi Miyoshi Station) on 1 June 1915. The company then pushed northeast, reaching the national railway's Hiroshima Station via a freight link on 15 July 1920 and Bingo-Shōbara on 8 December 1923. From early on it leaned on internal-combustion traction to compete with parallel buses, introducing gasoline railcars from 1929 and gaining authorization for diesel traction in May 1933 — foreshadowing the diesel character the line still has: never electrified, it is worked today by KiHa 120 and KiHa 40 (KiHa 47) series diesel multiple units running at up to 85 km/h over its entirely single-track, 1,067 mm narrow-gauge alignment.

The northern and central route was built or completed by the Japanese Government Railways (JGR). On 1 June 1933 the Geibi Railway's Bingo-Tōkaichi (now Miyoshi)–Bingo-Shōbara section was nationalized as the Shōbara Line, extended to Bingo-Ochiai by 20 December 1935. From the Okayama side, the government-built Sanshin Line opened between Bitchū-Kōjiro and Yagami on 10 February 1930. On 10 October 1936 the final Onuka–Bingo-Ochiai segment opened, completing the through route and absorbing the Shōbara Line into the Sanshin Line.

On 1 July 1937 the Geibi Railway's remaining Hiroshima–Bingo-Tōkaichi section was nationalized, the Sanshin Line absorbed it, and the unified line took the name Geibi Line under JGR control. Post-war it carried named express services across the mountains, such as the Chidori (from 1955) and Taishaku (from 1962), and the Bitchū-Kōjiro–Miyoshi section was de-steamed by 25 March 1971. On 1 April 1987, with the privatization of Japanese National Railways, the line passed to JR West, and one-person (wanman) operation was rolled out across it in 1991.

Under JR West the line's two faces diverged sharply. The Hiroshima-suburban end, Karuga–Hiroshima, became part of the Hiroshima City Network, entered the ICOCA IC-card area in 2007, and was given the line colour purple and route symbol "P"; the Miyoshi express was discontinued on 1 July 2007 and folded into the Miyoshi Liner rapid. Meanwhile the rural interior kept losing riders: the line-wide transport density (average passengers per day) fell from 2,561 in fiscal 1987 to 1,323 in fiscal 2019 and 1,194 in fiscal 2023 — an average that hides enormous variation between segments.

The most extreme case is the Tōjō–Bingo-Ochiai segment, where average daily transport density has sat in the single digits and low teens — about 8 in the mid-2010s, 11 in fiscal 2019, 20 in fiscal 2022 — one of the most lightly used pieces of railway in Japan. JR West's own disclosures put that segment's operating coefficient at 25,416 yen for the fiscal 2017–2019 average — over 25,000 yen spent to earn every 100 yen of revenue — against about 4,129 yen on the adjacent Bitchū-Kōjiro–Tōjō segment. The line has also been cut repeatedly by disaster: the July 2018 heavy rain destroyed the first Misasagawa bridge and closed the whole line until 23 October 2019, one year and three months later.

Citing this persistent low usage, JR West in June 2021 asked municipalities along the underused Bingo-Shōbara–Niimi sections to discuss the line's future, including bus alternatives; the first meeting was held on 5 August 2021. After local governments declined "no-preconditions" talks, JR West formally asked the national government on 3 October 2023 to convene a statutory "reconstruction council" under Japan's regional public-transport law — the first such request in the country — aiming to settle the section's future within about three years. As part of that process, demonstration bus services running parallel to four sections began on 1 June 2026.

• 191528 April: the private Geibi Railway opens its first section, Higashi-Hiroshima (a first-generation station, unrelated to the present Higashi-Hiroshima Station) to Shiwachi (36.7 miles / about 59.06 km). An extension from Shiwachi to Miyoshi (present Nishi Miyoshi Station) follows on 1 June 1915.
• 19238 December: the Geibi Railway is extended from Shiomachi to Bingo-Shōbara (about 16.09 km), having reached the national railway's Hiroshima Station via a freight link on 15 July 1920.
• 193010 February: the government-built Sanshin Line opens between Bitchū-Kōjiro and Yagami, the future Okayama-side end of the route. The Geibi Railway had begun using gasoline railcars in 1929 to compete with parallel bus services.
• 19331 June: the Geibi Railway's Bingo-Tōkaichi–Bingo-Shōbara section is nationalized and renamed the Shōbara Line. In May the Geibi Railway had also been authorized for diesel traction.
• 193520 December: the Shōbara Line is extended from Bingo-Saijō to Bingo-Ochiai (about 8.6 km).
• 193610 October: the Onuka–Bingo-Ochiai section opens, joining the line ends and completing the through route between Hiroshima and Bitchū-Kōjiro; the Shōbara Line is absorbed into the Sanshin Line.
• 19371 July: the Geibi Railway's Hiroshima–Bingo-Tōkaichi section is nationalized, the Sanshin Line absorbs it, and the unified line is renamed the Geibi Line under the Japanese Government Railways.
• 197125 March: the Bitchū-Kōjiro–Miyoshi section is de-steamed (converted away from steam traction). Centralized traffic control (CTC) was introduced over the whole line by 1983, with the control centre at Bingo-Shōbara.
• 19871 April: on the privatization of Japanese National Railways, the Geibi Line becomes part of the West Japan Railway Company (JR West).
• 1991One-person (wanman) driver-only operation is introduced — Niimi–Miyoshi on 1 April and Miyoshi–Hiroshima on 1 November.
• 20071 July: the Miyoshi express is discontinued and merged into the Miyoshi Liner rapid service. On 1 September the Karuga–Hiroshima section enters the ICOCA IC-card area.
• 20187 July: the July 2018 heavy rain destroys the first Misasagawa bridge between Shirakiyama and Karuga and puts the entire line out of service.
• 201923 October: the last closed section (Nakamita–Karuga) reopens, restoring full service one year and three months after the 2018 floods.
• 20218 June: citing low usage, JR West asks municipalities along the Bingo-Shōbara–Niimi sections to discuss the line's future, including bus alternatives; the first meeting is held on 5 August.
• 20233 October: JR West formally requests the national government to convene a statutory "reconstruction council" for the Bitchū-Kōjiro–Bingo-Shōbara section — the first such request in Japan — aiming to decide its future within about three years.
• 20261 June: the Geibi Line reconstruction council begins a weekday demonstration bus service running parallel to four sections of the line (a holiday/tourist demonstration service follows from 4 July).