Tsurumai Line

The line was built in stages from the late 1970s. Its first section, the 8.0-kilometre stretch between Fushimi and Yagoto in the centre and south of the city, opened on 18 March 1977, worked by newly introduced 3000 series trains. The following year, on 1 October 1978, the line was extended a further 5.4 kilometres south-east from Yagoto to Akaike, carrying it beyond the Nagoya city boundary into Nisshin.

Through-running onto a private railway followed almost immediately. On 29 July 1979 the Meitetsu Toyota New Line (今 the Toyota Line) opened from Akaike, and mutual through-services between it and the Tsurumai Line began the same day, linking the subway with Toyota. From Akaike, through trains run over the Toyota Line and then the Meitetsu Mikawa Line as far as Toyotashi Station.

Construction then continued north-westward from the city centre. On 27 November 1981 the 2.9-kilometre section from Jōshin to Fushimi opened, and on 6 September 1984 a further 2.7 kilometres were added from Shōnairyokuchikōen to Jōshin. The final piece, the 1.4-kilometre extension from Kami-Otai to Shōnairyokuchikōen, opened on 12 August 1993, completing the line at its full 20.4-kilometre length and establishing Kami-Otai as the north-western terminus.

The opening of the Kami-Otai end brought a second through-service: from 12 August 1993 the Tsurumai Line began mutual through-running with the Meitetsu Inuyama Line, and trains from Kami-Otai could continue north onto Meitetsu metals toward Iwakura, Fusō and Inuyama. In the same period the fleet was modernised, with 3050 series trains entering service in 1993; earlier, between 1987 and 1989, Sakura-dōri Line 6000 series trains had run on the Tsurumai Line on a provisional basis.

In the 2000s and 2010s the line saw a series of incremental upgrades and service adjustments. After Kami-Otai became an express stop on the Inuyama Line in 2001, the number of through-trains onto that line was reduced, and from 2008 daytime Inuyama-Line through-services were shortened to terminate at Iwakura. Newer N3000 series trains entered service on 16 March 2012, and platform departure indicators and approach melodies were rolled out across the stations during these years.

More recently the line's oldest stock and some of its through-running have been pared back. The original 3000 series trains were withdrawn in March 2023, and the timetable revision of 16 March 2024 abolished daytime and weekend through-services onto the Meitetsu Inuyama Line after 10 a.m. From 14 October 2024 movable platform-edge barriers began to be brought into use station by station starting at Shōnairyokuchikōen, a programme completed on 8 June 2026 when platform doors were installed at Akaike, the line's south-eastern terminus.

• 197718 March: the first section, Fushimi–Yagoto (8.0 km), opens; 3000 series trains enter revenue service.
• 19781 October: the line is extended south-east from Yagoto to Akaike (5.4 km), crossing the Nagoya city boundary into Nisshin.
• 197929 July: the Meitetsu Toyota New Line (now the Toyota Line) opens from Akaike, and mutual through-running with the Tsurumai Line begins the same day.
• 198127 November: the Jōshin–Fushimi section (2.9 km) opens, extending the line north-west from the centre.
• 19846 September: the Shōnairyokuchikōen–Jōshin section (2.7 km) opens.
• 198728 December: Sakura-dōri Line 6000 series trains begin provisional service on the Tsurumai Line (running until 1989).
• 19931 April: 3050 series trains enter revenue service.
• 199312 August: the final section, Kami-Otai–Shōnairyokuchikōen (1.4 km), opens, completing the line; mutual through-running with the Meitetsu Inuyama Line begins.
• 20011 October: after Kami-Otai becomes an express stop on the Inuyama Line, the number of through-trains onto that line is reduced.
• 200827 December: daytime through-services onto the Inuyama Line are shortened to terminate at Iwakura.
• 201216 March: N3000 series trains enter revenue service.
• 2023March: the original 3000 series trains are withdrawn from service.
• 202416 March: a timetable revision abolishes daytime and weekend (after 10 a.m.) through-services onto the Meitetsu Inuyama Line.
• 202414 October: movable platform-edge barriers begin to be brought into use station by station, starting at Shōnairyokuchikōen.
• 20268 June: the platform-door programme is completed with the installation of barriers at Akaike, the south-eastern terminus.