IR Ishikawa Railway Line

The route began as a segment of the state-built Hokuriku Line. On 1 November 1898 the government railway's Kanazawa–Takaoka section opened, a stretch of about 40.82 km that included the present line's northern end through Tsubata; Tsubata Station opened the same day. In 1905 trains of the Nanao Railway began running through between Tsubata and Kanazawa, and on 15 June 1909 the Kurikara signal post, opened the previous year, was upgraded to Kurikara Station. On 12 October 1909 the national railway line-naming rules designated the Maibara–Uozu and Tsuruga–Kanegasaki sections as the Hokuriku Main Line, the name the corridor would carry for more than a century.

Through the early and mid-twentieth century the line was progressively double-tracked and electrified. The Kanazawa–Tsubata section was doubled on 1 October 1938, the Ishido–Kurikara section in 1960 and the Tsubata–Kurikara section in 1962. On 24 August 1964 the Kanazawa–Kurikara stretch was electrified with 20 kV AC, and by 1969 the whole route was double-tracked and electrified. When Japanese National Railways was privatised on 1 April 1987, the Maibara–Naoetsu section of the Hokuriku Main Line (353.9 km) passed to the West Japan Railway Company (JR West), while Japan Freight Railway (JR Freight) became a Type-II railway operator over the same tracks.

Planning for the conversion to a third-sector railway followed the decision to extend the Hokuriku Shinkansen to Kanazawa. The Ishikawa Prefecture Parallel Conventional Line Company was established on 28 August 2012 to take over the parallel conventional line, and on 1 August 2013 it was renamed the IR Ishikawa Railway Company. In December 2013 the company applied to the Ministry of Land, Infrastructure, Transport and Tourism for a Type-I railway business licence over the 17.8 km between Kurikara and Kanazawa, and on the same day JR West filed notice to discontinue its Kanazawa–Naoetsu service on the opening of the Shinkansen; the licence was granted on 28 February 2014.

The first transfer took place on 14 March 2015, when the Hokuriku Shinkansen extension from Nagano to Kanazawa opened. On that day the Kurikara–Kanazawa section of the Hokuriku Main Line — 17.8 km with five stations — was separated from JR West as a parallel conventional line and reopened as the IR Ishikawa Railway Line. The company introduced its "Ainokaze Liner" service two days later, and on 15 April 2017 IC card travel with ICOCA became available across the whole line.

The line reached its present extent with the second Shinkansen stage. On 16 March 2024 the Hokuriku Shinkansen extension from Kanazawa to Tsuruga opened, and the Kanazawa–Daishōji section of the Hokuriku Main Line — 46.4 km with fourteen stations — was separated from JR West and incorporated into the IR Ishikawa Railway Line. Nishi-Matsutō Station opened on the same day and one-man operation began across the entire line, bringing the route to its current length of 64.2 km. From 15 March 2025 the company began running rapid services between Kanazawa and Daishōji.

Today the IR Ishikawa Railway Line forms the Ishikawa-Prefecture link in the chain of third-sector railways that inherited the Hokuriku Main Line after the Shinkansen reached the Sea-of-Japan coast, connecting with the Ainokaze Toyama Railway to the north-east and with JR West's remaining Hokuriku-area lines, including the Nanao Line, in and around Kanazawa. Alongside its passenger services it remains an important freight artery, with JR Freight running through trains over the line and serving the Kanazawa Freight Terminal, which opened in 2003.

• 18981 November: the government railway's Kanazawa–Takaoka section (about 40.82 km) opens, including the present line's northern end; Tsubata Station opens the same day.
• 190915 June: the Kurikara signal post (opened 1908) is upgraded to Kurikara Station. 12 October: national line-naming rules designate the corridor part of the Hokuriku Main Line.
• 19381 October: the Kanazawa–Tsubata section is double-tracked; Hanazono signal station is abolished.
• 196424 August: the Kanazawa–Kurikara section is electrified at 20 kV AC.
• 19871 April: on the privatisation of Japanese National Railways, the Maibara–Naoetsu section of the Hokuriku Main Line (353.9 km) passes to JR West; JR Freight becomes a Type-II operator over the line.
• 200312 June: Kanazawa Freight Terminal Station opens.
• 201228 August: the Ishikawa Prefecture Parallel Conventional Line Company is established to take over the parallel conventional line.
• 20131 August: the company is renamed the IR Ishikawa Railway Company. December: it applies for a Type-I licence over the 17.8 km Kurikara–Kanazawa section.
• 201428 February: IR Ishikawa Railway obtains its Type-I railway business licence for the 17.8 km Kurikara–Kanazawa section.
• 201514 March: with the Hokuriku Shinkansen extended from Nagano to Kanazawa, the Kurikara–Kanazawa section (17.8 km, 5 stations) is separated from JR West and reopens as the IR Ishikawa Railway Line.
• 201715 April: IC card travel with ICOCA becomes available across the whole line.
• 202416 March: with the Hokuriku Shinkansen extended from Kanazawa to Tsuruga, the Kanazawa–Daishōji section (46.4 km, 14 stations) is separated from JR West and incorporated into the line; Nishi-Matsutō Station opens and one-man operation begins line-wide.
• 202515 March: rapid (kaisoku) services begin running between Kanazawa and Daishōji.