Tosaiwahara

Known weekday departures: 8/day · Known Sat & holiday departures: 8/day

First / last known departure (weekday): 6:10 / 20:37

Busiest hour (known departures): 8:00–9:00 (2)

0:00 ─ 23:00

Figures are the departures known from the timetable data, not a count of today's actual service.

Timetable data as of 2 May 2026 (retrieved in spring/summer 2026).

• Dosan Line: Oboke ⇄ Toyonaga

Tosa-Iwahara Station opened on 28 November 1935 when the then-Kōchi Line was extended north from Toyonaga to Minawa and the through-route was renamed the Dosan Line. Japanese Government Railways operated the station, with control passing to Japanese National Railways after the war. The station was made unstaffed on 1 October 1970 and converted to simple consignment. On 26 December 1986, Ōtoyo Agricultural Cooperative paid the entire 15 million yen cost of a new combined station-cum-cooperative office building. With the privatisation of JNR on 1 April 1987, operation passed to JR Shikoku, which has since assigned the station the number D28.

Tosa-Iwahara is the northernmost station in Kōchi Prefecture, and between 1974 and 1992 — the gap between the closure of the Tosa Electric Railway's Aki Line and the opening of the Asa Kaigan Railway's Asatō Line — it was also the easternmost.