Wakayamakō Line

The line opened on 6 May 1956, in the same year that Nankai inaugurated its ferry route to Shikoku, running from Wakayamashi to a first-generation Wakayama Port station (later renamed Chikkōchō). It was built so that rail passengers could reach the new ferry, and through trains from Namba on the Nankai Main Line served the connection from the outset; the earliest of these was an express named “Awa” worked by 1551-series cars, later joined by the limited express “Shikoku”.

On 6 March 1971 the line was extended beyond Chikkōchō to a new terminus at Suiken, taking the route to 5.4 km. The extension was carried out by Wakayama Prefecture in connection with the relocation of the port and a planned timber-transport scheme, and at the same time the original Wakayama Port station was relocated and renamed Chikkōchō while a second-generation Wakayamakō opened on the through line. By the time the extension opened, however, the timber traffic had already shifted to road haulage, and no freight train ever ran on it.

The unusual ownership of the line dates from this period: the Wakayamashi-to-Kubochō section (0.8 km) remained Nankai's own railway, but the Kubochō-to-Wakayamakō portion (2.0 km) was built by Wakayama Prefecture as a harbour railway, the prefecture taking over Nankai's construction licence. As a result Nankai is the Class-1 operator on the inner section and a Class-2 operator on the harbour section, while Wakayama Prefecture is the Class-3 owner of the harbour section. Operations were modernised over time, with a programmed traffic-control (PTC) system introduced on 1 September 1980 and one-man (driver-only) operation of local trains beginning on 24 March 2001.

The Suiken extension was always lightly used — only two return local trips a day ran the full length — and on 26 May 2002 the 2.6-kilometre Wakayamakō–Suiken section was closed, the stated reason being that a level crossing on it obstructed the widening of an adjoining road. Special services marked the closing: a one-off limited express “Southern” ran from Namba all the way to Suiken on 28 April 2002, and on the section's final day of operation extra trains supplemented the regular two round trips. No freight had ever used the section in its three decades.

The line's three intermediate stations — Kubochō, Tsukijibashi and Chikkōchō — were closed on 27 November 2005 because each averaged fewer than a hundred boardings a day, and Wakayama Bus services took over much of their role. With the intermediate stops gone, in-line local trains were withdrawn, leaving only the through limited expresses and expresses; the former Kubochō site became simply the “Prefecture–Company Boundary” (県社分界点) marking the change of ownership. From 1 April 2012 the timetable was reorganised entirely around ferry connections, services were thinned, weekend and holiday expresses were dropped, in-line local trains returned in place of some “Southern” and express runs, and Wakayamakō Station became unstaffed.

Today the Wakayamakō Line is worked by Nankai Main Line through limited expresses “Southern” (since 1985) and, on weekdays, expresses to and from Namba, together with local trains shuttling within the line; the local stock is operated in common with the Kada Line. Since 29 August 2023 Nankai has used the line, together with the signalling maker Kyosan Electric, for an autonomous-driving demonstration with 8300-series trains. When Nankai Ferry announced on 30 March 2026 that it would withdraw from the Shikoku ferry route, Nankai stated that the Wakayamakō Line would nonetheless remain and that there was no plan to close it.

• 19566 May: the line opens between Wakayamashi and the first-generation Wakayama Port station (later Chikkōchō), the same year Nankai's Shikoku ferry route begins.
• 19716 March: the line is extended from Chikkōchō to Suiken (reaching 5.4 km) by Wakayama Prefecture; the original Wakayama Port station is relocated and renamed Chikkōchō and a second-generation Wakayamakō opens.
• 197131 March: the connecting Nankai Wakayama Tramway Line at Wakayamashi Station ceases.
• 19801 September: a programmed traffic-control (PTC) system is introduced on the line.
• 200124 March: one-man (driver-only) operation of local trains begins.
• 200226 May: the 2.6 km Wakayamakō–Suiken section is closed, reportedly because a level crossing on it obstructed the widening of an adjoining road; no freight train ever ran on it.
• 200527 November: the three intermediate stations Kubochō, Tsukijibashi and Chikkōchō are closed for low ridership (under 100 boardings a day each); in-line local trains are withdrawn and the former Kubochō becomes the 'Prefecture–Company Boundary'.
• 20121 April: the timetable is reorganised around ferry connections, services are reduced, weekend/holiday expresses are dropped, in-line local trains return in place of some 'Southern' and express runs, and Wakayamakō Station becomes unstaffed.
• 202329 August: Nankai begins an autonomous-driving demonstration on the line with the signalling maker Kyosan Electric, using an 8300-series train.
• 202630 March: Nankai Ferry announces it will withdraw from the Shikoku ferry route; Nankai states the Wakayamakō Line will remain, with no plan to close it.