Kita-Ōsaka Kyūkō Namboku Line

The line was conceived as transport for Expo '70, the Japan World Exposition held on the Senri Hills in Suita in 1970. Planning began on 23 May 1966 as part of the exposition's preparatory works, when committees proposed a new railway directly linking central Osaka to a station near the fairground's symbol zone. The route was originally envisaged simply as an extension of the Midōsuji Line, but because it ran beyond the Osaka city limits the municipal government could not build it alone, raising problems of land expropriation and finance. After the Ministry of International Trade and Industry intervened, a comparatively economical plan put forward by Hankyu was adopted, and on 11 December 1967 the Kita-Ōsaka Kyūkō Railway Company was incorporated under the Local Railway Act as a joint venture between the City of Osaka and Hankyu, brokered by Takeo Miki, then Minister of International Trade and Industry.

Construction of the Esaka–Expo Central Gate line began on 16 July 1968, and test running over the full route had begun by December 1969. The line opened on 24 February 1970, connecting Esaka, then the northern terminus of the Midōsuji Line, with the grounds of Expo '70, and through service with the Midōsuji Line began the same day. During the exposition the section north of a junction near present-day Senri-Chūō was worked as the Kaijō (Venue) Line to a terminus at Expo Central Gate, using ground that would later become the up carriageway of the Chūgoku Expressway. At opening the temporary Senri-Chūō station stood on the Kaijō Line rather than at its present site.

When the exposition closed, the Kaijō Line between the junction and Expo Central Gate was abandoned on 14 September 1970 and a short link to the permanent Senri-Chūō Station was opened in its place, giving the line broadly its present form; removal of the venue line was completed that December and its right-of-way was handed over for the Chūgoku Expressway, whose construction cost the railway almost nothing. Because the heavy Expo traffic had let the company recoup much of its building cost during the fair, the Esaka–Senri-Chūō section has long been able to charge unusually low fares. An intermediate station, Ryokuchi-kōen, was added on 30 March 1975.

Over the following decades the line's rolling stock and capacity were progressively upgraded while the route itself stayed fixed at Esaka–Senri-Chūō. The 8000 series "Pole Star" trains entered service on 1 July 1986, and in 1987 the company was promoted from a minor to a semi-major private railway. The original 2000 series, in service since the 1970 opening, was withdrawn in 1993, and ten-car operation began on 9 December 1996. Through running with the Midōsuji Line tied the line's timetable ever more closely to that of the Osaka Metro, and no trains turn back within the line itself.

From the late 1980s the city of Minoh pressed for the line to be extended north, and the proposal was given formal weight in transport plans from 1989. After many years of study, a four-party basic agreement between Osaka Prefecture, the city of Minoh, the Kita-Ōsaka Kyūkō Railway and Hankyu was signed on 31 March 2014, and to provide the extra trains the line would need the company introduced the 9000 series "Pole Star II", which entered service on 28 April 2014. Construction of the 2.5-kilometre extension from Senri-Chūō to Minoh-Kayano began on 19 January 2017, and on 24 July 2018 its two new stations were named Minoh-Semba Handai-mae and Minoh-Kayano.

The extension's opening, originally targeted for 2020, was put back to fiscal 2023 in May 2019 because of land-acquisition delays and obstacles found during construction. The Senri-Chūō–Minoh-Kayano section finally opened on 23 March 2024, completing the line at 8.4 km and extending through services from the Midōsuji Line north to Minoh-Kayano. The line was built as an ordinary railway under railway law, but the 1.2 km nearest Minoh-Kayano was licensed instead as a tramway under the Tramway Act, because it follows the Shin-Midōsuji road and was built in the guise of road improvement. The extension was financed in large part by the city of Minoh, and the long-standing low fares on the original section were left unchanged.

• 196623 May: planning for the line begins as part of the preparatory works for Expo '70, with a proposal for a new railway directly linking central Osaka to a station near the fairground.
• 196711 December: the Kita-Ōsaka Kyūkō Railway Company is incorporated under the Local Railway Act as a joint venture of the City of Osaka and Hankyu, brokered by MITI Minister Takeo Miki; a local-railway licence had been granted on 13 October.
• 196816 July: construction of the Esaka–Expo Central Gate line begins.
• 196917 December: test running begins over the full route (staged test runs had started in September).
• 197024 February: the Namboku Line and Kaijō (Venue) Line open between Esaka and Expo Central Gate (9.0 km), and through service with the Midōsuji Line begins; the first Senri-Chūō station is a temporary one on the Kaijō Line.
• 197014 September: with the exposition over, the Kaijō Line (junction–Expo Central Gate, 3.6 km) is abandoned and a link to the permanent Senri-Chūō Station opens; the venue-line right-of-way is later repurposed for the Chūgoku Expressway.
• 197530 March: Ryokuchi-kōen Station opens as an intermediate station.
• 19861 July: the 8000 series "Pole Star" trains enter service. (English Wikipedia dates them from 1987; the Japanese-language source gives 1986, which is used here.)
• 1987The company is promoted from a minor private railway to a semi-major private railway.
• 19932 October: the original 2000 series, in service since the 1970 opening, is withdrawn.
• 19969 December: ten-car operation begins.
• 201431 March: a four-party basic agreement on the extension is signed by Osaka Prefecture, the city of Minoh, the Kita-Ōsaka Kyūkō Railway and Hankyu. 28 April: the 9000 series "Pole Star II" enters service.
• 201719 January: construction begins on the 2.5 km extension from Senri-Chūō to Minoh-Kayano, with one intermediate station.
• 201824 July: the two new stations on the extension are named Minoh-Semba Handai-mae and Minoh-Kayano.
• 20197 May: the extension's opening is put back from the original 2020 target to fiscal 2023 because of land-acquisition delays and obstacles found during construction.
• 202423 March: the Senri-Chūō–Minoh-Kayano section (about 2.5 km) opens, completing the line at 8.4 km; the section nearest Minoh-Kayano (1.2 km) is licensed as a tramway under the Tramway Act.