Ōwani Line

The line was not built by the Kōnan Railway but by an earlier company, the Hirosaki Electric Railway, which was established on 25 July 1949. Its founding capital came from a combination of the Hirosaki city government and Mitsubishi Electric, and the project carried a second purpose beyond local transport: Mitsubishi intended the line to serve as a test platform, or technology demonstration, for future local electric-railway systems. After several years of construction the railway opened its full route between Ōwani and Chūō-Hirosaki on 26 January 1952.

On 1 October 1970 the Hirosaki Electric Railway was transferred to the Kōnan Railway, and the route became that company's Ōwani Line. At the same time freight operations on the line were discontinued, leaving it a passenger-only railway. The Kōnan Railway already operated a separate route in the area, its Kōnan Line out of Hirosaki, and the Ōwani Line joined it as the company's second line.

Under Kōnan Railway ownership the line was steadily modernised and reorganised. In November 1972 a new depot and inspection works, the Tsugaru-Ōsawa rolling-stock depot, was opened within Tsugaru-Ōsawa Station, replacing the old Nishi-Hirosaki shed inherited from the Hirosaki Electric Railway era. Jōnan Station opened on 1 December 1973, and automatic block signalling was introduced on 2 October 1976. A rapid (express) service was introduced on 1 October 1981, and Gijuku-Kōkō-mae Station opened on 1 November 1987. Several stations were renamed along the way — among them Kōnan-Ōwani to Ōwani on 1 April 1986 — and one-man (driver-only) operation began on 1 October 1991.

From the 2000s the line came under growing pressure from falling ridership, and its service was gradually pared back. An automatic train stop (ATS) system came into use on 1 November 2003. The rapid service that had run since 1981 was abolished in November 2006, and timetables were thinned, with through-day frequencies reduced. In 2008 two more stations were renamed, Jōnan becoming Seiai-Chūkō-mae and Nishi-Hirosaki becoming Hirosaki-Gakuin-Daimae, both on 1 September. By 2013 the operator had publicly stated its intention to close the line because of the decline in passengers. Station numbering, with the line code "KW", was introduced on 5 October 2020.

In its later years the Ōwani Line was repeatedly disrupted by accidents and track problems. A derailment on 14 April 2019 suspended the whole line, and a timetable revision later that year cut services further and lengthened journey times. In 2023 the line suffered another derailment in August and a rail defect discovered in September, each forcing temporary suspensions before services were fully restored that December.

On 27 November 2024 the Kōnan Railway announced that it would suspend the entire Ōwani Line — in effect abolishing it — at the end of fiscal year 2027, that is, in March 2028. Operation is planned to cease with the last trains running the day before, and the line is to be indefinitely suspended from 1 April 2028, bringing to an end more than seventy years of service through Hirosaki's apple country.

• 194925 July: the Hirosaki Electric Railway is established, funded by the Hirosaki city government and Mitsubishi Electric, the latter intending the line as a test platform for future local electric-railway systems.
• 195226 January: the Hirosaki Electric Railway opens its line between Ōwani and Chūō-Hirosaki.
• 19701 October: the line is transferred to the Kōnan Railway, becoming its Ōwani Line; freight operations are discontinued.
• 1972November: the Tsugaru-Ōsawa rolling-stock depot and inspection works opens at Tsugaru-Ōsawa Station, replacing the former Nishi-Hirosaki shed.
• 19731 December: Jōnan Station opens.
• 19762 October: automatic block signalling is introduced on the line.
• 19811 October: a rapid (express) service begins operating on the line.
• 19861 April: several stations are renamed, including Kōnan-Ōwani to Ōwani.
• 19871 November: Gijuku-Kōkō-mae Station opens.
• 19911 October: one-man (driver-only) operation begins.
• 20031 November: an automatic train stop (ATS) system comes into use.
• 2006November: the rapid service that had run since 1981 is abolished and timetables are thinned.
• 20081 September: Jōnan Station is renamed Seiai-Chūkō-mae and Nishi-Hirosaki Station is renamed Hirosaki-Gakuin-Daimae.
• 2013The Kōnan Railway publicly states its intention to close the line owing to declining ridership.
• 201914 April: a derailment suspends the whole line; a later timetable revision that year reduces services and lengthens journey times.
• 20205 October: station numbering, with the line code 'KW', is introduced.
• 2023A derailment in August and a rail defect found in September each force temporary suspensions; full service is restored on 8 December.
• 202427 November: the Kōnan Railway announces it will suspend (in effect abolish) the entire Ōwani Line at the end of FY2027, i.e. March 2028.
• 20281 April: the line is to be indefinitely suspended, with the last trains running the previous day.