Shinano Railway Line

The railway through this valley is old. It opened on 15 August 1888 as a government line between Ueda and Shinonoi (continuing to Nagano), and on 1 December 1888 the section from Karuizawa to Ueda was added, completing the route across what is now the Shinano Railway. In its first decades it carried the trunk traffic of a much longer corridor: when a line-naming scheme was introduced on 12 October 1909 the whole Takasaki–Niigata route was designated the Shin'etsu Line, and on 1 June 1914 it was renamed the Shin'etsu Main Line, the name it would keep for over eighty years.

Through the first half of the twentieth century the line was gradually built up. New stations were inserted along the route — Ōya in 1896, the forerunner of Shinano-Oiwake in 1909, the forerunner of Naka-Karuizawa (Kutsukake) in 1910, Togura in 1912, Shigeno in 1923, and others — and several of the original names were later changed, Kutsukake becoming Naka-Karuizawa and Kita-Shiojiri becoming Nishi-Ueda in 1956.

Modernisation came after the Second World War. The Karuizawa–Shinonoi section was electrified at 1,500 V DC on 21 June 1963. Double-tracking then proceeded segment by segment from the late 1960s onward, beginning with Karuizawa–Naka-Karuizawa in 1967 and finishing with the Togura–Yashiro stretch on 29 June 1982, at which point the entire Karuizawa–Shinonoi line was double-tracked. When Japanese National Railways was divided and privatised on 1 April 1987, the line passed to the East Japan Railway Company (JR East), while Japan Freight Railway (JR Freight) took over as a secondary operator for freight east of the present Tanaka area.

The decisive change came with the Shinkansen. On 1 October 1997 the Nagano Shinkansen (the Takasaki–Nagano section of the Hokuriku Shinkansen, so called before the extension to Kanazawa) opened, and the parallel conventional Karuizawa–Shinonoi section was separated from JR East and reopened the same day as the Shinano Railway Line. The third-sector operator Shinano Railway, majority-owned by Nagano Prefecture, had been established on 1 May 1996 to take it over. This was the first time a parallel conventional line was hived off from JR at the opening of a Shinkansen — the template for many later transfers. On conversion the line's measured length was revised from the 65.6 km of the JR era to 65.1 km.

Under Shinano Railway the line was reshaped for commuter service. Its first independent timetable revision, on 8 December 1998, introduced the "Shinano Sunliner" rapid (later split into the "Shinano Sunrise" and "Shinano Sunset" services), and a string of new stations was opened to lift ridership: Tekuno-Sakaki in 1999, Yashiro-kōkō-mae in 2001, Shinano-Kokubunji in 2002 and Chikuma in 2009. Driver-only operation began on the Karuizawa–Komoro section on 5 January 2004 and was progressively extended; the inherited 169 series electric multiple units bowed out of regular service in 2013, replaced by 115 series and, from 2020, new SR1 series trains. Centralised traffic control covering the whole line was commissioned in 2001.

In 2015 Shinano Railway gained a second line. When the Hokuriku Shinkansen was extended from Nagano to Kanazawa on 14 March 2015, the parallel Nagano–Myōkō-Kōgen section of the Shin'etsu Main Line was separated from JR East and opened as the Shinano Railway Kita-Shinano Line; the original line's name and signage were unaffected, and a handful of trains run through between the two via Nagano. More recently the line has had to cut its cloth to falling ridership and the effects of the COVID-19 pandemic: a far-reaching revision on 18 March 2023 thinned services and lowered the maximum speed from 100 to 85 km/h, and on 14 March 2026 the Suica IC card was introduced across the whole line. The line was also closed in its entirety by Typhoon Hagibis in October 2019, reopening fully on 15 November 2019.

• 188815 August: a government railway opens between Ueda and Shinonoi (running on to Nagano), the first section of the present line.
• 18881 December: the Karuizawa–Ueda section opens, completing the route across what is now the Shinano Railway Line.
• 190912 October: a line-naming scheme designates the whole Takasaki–Niigata route the Shin'etsu Line.
• 19141 June: the route is renamed the Shin'etsu Main Line.
• 196321 June: the Karuizawa–Shinonoi section (continuing to Nagano) is electrified at 1,500 V DC.
• 198229 June: with the Togura–Yashiro stretch double-tracked, the entire Karuizawa–Shinonoi line becomes double-track.
• 19871 April: with the privatisation of Japanese National Railways, the line passes to JR East; JR Freight becomes a secondary (Type 2) operator for freight.
• 19961 May: the third-sector operator Shinano Railway, majority-owned by Nagano Prefecture, is established to take over the line.
• 19971 October: the Nagano Shinkansen opens; the parallel Karuizawa–Shinonoi section is separated from JR East and reopens as the Shinano Railway Line — the first conventional line ever hived off from JR at a Shinkansen opening. Its length is revised from 65.6 km to 65.1 km.
• 19988 December: the first post-transfer timetable revision introduces the 'Shinano Sunliner' rapid service.
• 19991 April: Tekuno-Sakaki Station opens between Nishi-Ueda and Sakaki.
• 20011 February: centralised traffic control (CTC) is introduced over the whole line; on 22 March, Yashiro-kōkō-mae Station opens.
• 200229 March: Shinano-Kokubunji Station opens between Ōya and Ueda.
• 20045 January: driver-only operation begins on some trains on the Karuizawa–Komoro section, later progressively extended.
• 200914 March: Chikuma Station opens between Togura and Yashiro.
• 201316 March: the inherited 169 series EMUs leave regular service (last regular run 29 April 2013), replaced by 115 series trains.
• 201514 March: with the Hokuriku Shinkansen extended from Nagano to Kanazawa, the parallel Nagano–Myōkō-Kōgen section is separated from JR East and opens as the Shinano Railway Kita-Shinano Line, the company's second line.
• 201912 October: Typhoon Hagibis suspends the entire line; full service is restored on 15 November 2019.
• 202318 March: a far-reaching revision thins services and lowers the maximum speed from 100 to 85 km/h.
• 202614 March: the Suica IC card is introduced across the whole line.