Keihanna Line

The line's origins lie in plans to push Osaka's subway network east toward Ikoma. On 23 March 1977 Kintetsu obtained the tramway licence for the Nagata–rail/tram boundary section and the railway licence for the boundary–Ikoma section, and on 16 September 1977 a dedicated company, Higashi-Osaka Ikoma Railway, was established to build the route; the licences were transferred to it later that year. Construction of what was then called the Higashi-Osaka Line began with a groundbreaking ceremony on 16 September 1982. To match the existing subway, the new line was laid to standard gauge and equipped with third-rail current collection rather than Kintetsu's usual narrow-gauge, overhead-wire arrangement.

On 1 April 1986 Kintetsu absorbed the Higashi-Osaka Ikoma Railway by merger, and on 1 October 1986 the Higashi-Osaka Line opened between Nagata and Ikoma, immediately beginning reciprocal through operation with the Osaka Municipal Subway (now Osaka Metro) Chūō Line as far as Ōsakakō. The Higashi-Osaka depot at Higashi-Ikoma opened the same day. The new line bored through the Ikoma range, replacing the role once played by Kintetsu's older mountain crossings and giving the eastern suburbs a direct subway link to the heart of Osaka.

Less than a year after opening, the line suffered its worst accident: on 21 September 1987 an electrical fault inside the Ikoma Tunnel started a cable fire, stranding a train in the tunnel; one person was killed and forty-eight were injured. Service patterns were steadily strengthened thereafter. From 15 March 1990 the daytime Chūō Line trains that had previously turned back within the subway were extended so that every train ran through onto the Higashi-Osaka Line, and on 18 December 1997 the through-service was lengthened westward to Cosmosquare when the Osaka Port Transport System's Technoport Line opened.

Attention then turned to extending the line itself eastward into the new Kansai Science City. A second company, Nara Ikoma Rapid Railway, was founded on 28 July 1998 to own the extension, and that September it took the third-sector railway licence for the Ikoma–Tomigaoka section while Kintetsu took the operating licence, the project being known as the Keihanna New Line. Construction began in October 2000. The works were substantial, including the 3,600-metre Higashi-Ikoma Tunnel, which was holed through on 26 August 2004, and a new 7020-series fleet entered service on 1 December 2004 ahead of the opening.

On 31 January 2005 Kintetsu announced the formal line name "Keihanna Line" together with the names of the three new stations, and a unified nickname, "Yumehanna," was later adopted for the combined Keihanna Line and Chūō Line corridor. The extension opened on 27 March 2006: the Ikoma–Gakken Nara-Tomigaoka section entered service, the former Higashi-Osaka Line was renamed the Keihanna Line over its whole Nagata–Gakken Nara-Tomigaoka length, and one-man operation began on the Kintetsu section. The Tomigaoka depot and new signal posts opened at the same time.

In the years that followed the line was integrated into Kansai's contactless-fare ecosystem, with PiTaPa and ICOCA accepted from 1 April 2007, and timetables were repeatedly revised to add morning-peak services toward Gakken Nara-Tomigaoka. The line's resilience was tested on 28 June 2024 when heavy rain triggered a landslide between Ikoma and Shiraniwadai, suspending the whole line; service was restored in stages, with the Nagata–Shin-Ishikiri section reopening on 29 June and the remainder on 1 July.

The line's defining feature — its through-running with the Chūō Line — continues to expand its reach. On 19 January 2025 the through-service was extended to the newly opened Yumeshima Station, in step with the Osaka Metro Chūō Line's own extension to the artificial island, lengthening the one-seat journey available from the Nara hills all the way across Osaka Bay. Today the Keihanna Line remains a compact but strategically important commuter route, jointly using Kintetsu's 7000- and 7020-series trains and Osaka Metro's own rolling stock to link the Science City with central Osaka.

• 197716 September: Higashi-Osaka Ikoma Railway is established to build the line (Kintetsu having obtained the Nagata–Ikoma tramway and railway licences on 23 March).
• 198216 September: groundbreaking ceremony for construction of the Higashi-Osaka Line.
• 19861 April: Kintetsu absorbs the Higashi-Osaka Ikoma Railway by merger.
• 19861 October: the Higashi-Osaka Line opens from Nagata to Ikoma, beginning through operation onto the Osaka Municipal Subway Chūō Line as far as Ōsakakō; the Higashi-Ikoma depot opens.
• 198721 September: an electrical fault causes a cable fire in the Ikoma Tunnel, stranding a train; one person is killed and 48 injured.
• 199015 March: daytime Chūō Line trains that had turned back within the subway are extended so that all trains run through onto the Higashi-Osaka Line.
• 199718 December: with the opening of the Osaka Port Transport System Technoport Line, the through-service is extended west to Cosmosquare.
• 199828 July: Nara Ikoma Rapid Railway is founded to own the planned eastward extension; in September it takes the Ikoma–Tomigaoka third-sector licence (the 'Keihanna New Line').
• 2000October: construction of the Keihanna New Line (Ikoma–Tomigaoka extension) begins.
• 200426 August: the 3,600 m Higashi-Ikoma Tunnel is holed through; on 1 December the new 7020 series enters revenue service.
• 200531 January: Kintetsu announces the formal line name 'Keihanna Line' and the names of the three new stations.
• 200627 March: the Ikoma–Gakken Nara-Tomigaoka extension opens; the Higashi-Osaka Line is renamed the Keihanna Line over its whole length, and one-man operation begins on the Kintetsu section.
• 20071 April: PiTaPa and ICOCA contactless fare cards become usable at all stations.
• 202428 June: heavy rain triggers a landslide between Ikoma and Shiraniwadai, suspending the whole line; service is restored to Shin-Ishikiri on 29 June and fully on 1 July.
• 202519 January: with the Osaka Metro Chūō Line's extension to Yumeshima, the through-service is extended to the new Yumeshima Station.