Mt. Akaiwa

Mount Akaiwa (Akaiwadake, 2,769 m) stands in the Jonen range of the southern North Alps, in Nagano. One of Japan’s 100 Highest Mountains, it rises between Mount Otensho and Mount Nishi on the “Omote-Ginza” traverse that links Mount Tsubakuro and Mount Yari. Because the trail bypasses the summit on its east side, few hikers actually stand on top — a quiet peak looking out at the Yari–Hotaka ridgeline.

*Timetable last checked: 2026-06-14

1. [Outbound] Hotaka Station → Nakabusa Onsen (Tsubakuro trailhead)

Bus TimetableHotaka Station → Ariakeyama-jinja → Nakabusa Onsen

You board the Nakabusa Line shared bus in front of Hotaka Station. A debris flow on 8 August 2026 washed away the Kurokawa Bridge on the Nakabusa prefectural road, so a temporary timetable applies from 22 August until further notice. The bus from Hotaka Station now runs only as far as Ariakeyama-jinja; from there you change to a nine-seat jumbo taxi for Nakabusa Onsen. The connection is immediate, with no waiting time. The fare to Nakabusa Onsen is unchanged at ¥1,500 one way, and the ticket you buy at Hotaka Station is also used on the connecting taxi (show it to the driver). Reservation required. Times differ between “A-schedule days” (Saturdays, Sundays and public holidays) and “B-schedule days” (other weekdays). The road closes when it rains and no buses run — see the access status at the top of this article.

Reference : Azumino City Tourism Association — reopening of the Nakabusa road and the temporary bus timetable (with the A/B calendar)

2. [Outbound] Takebashi Station → Nakabusa Onsen (night bus)

Night BusTakebashi → Mt. Tsubakuro Trailhead / Nakabusa Onsen

The overnight “Mainichi Alpen-go” runs from Tokyo (reservation required, seasonal). Because of the collapse on the Nakabusa prefectural road it no longer runs through to Nakabusa Onsen for departures from 21 August 2026. You change to the scheduled bus at Hotaka Station. The bus fare between Hotaka Station and Nakabusa Onsen is included in the tour price, and the ticket is handed to you when you leave Takebashi. The fare is ¥11,000–17,000 outbound, depending on the season and seat.

Reference : Mainichi Alpen-go — Tsubakuro / Jōnen area (outbound)

3. [Return] Nakabusa Onsen → Hotaka Station

Bus TimetableNakabusa Onsen → Ariakeyama-jinja → Hotaka Station

The return uses the same temporary timetable. You take the connecting jumbo taxi from Nakabusa Onsen down to Ariakeyama-jinja and change there to the shared bus for Hotaka Station. Return times are the same on A-schedule and B-schedule days. ¥1,500 one way, reservation required.

Reference : Azumino City Tourism Association — reopening of the Nakabusa road and the temporary bus timetable (with the A/B calendar)

4. Climbing route, the crux and estimated trail times of Mount Akaiwa

The starting point for Mount Akaiwa is Nakabusa Onsen. Climb the Kassen ridge to Mount Tsubakuro and Enzanso, follow the Omote-Ginza traverse to Mount Otensho (Daitenso, Daitensho Hütte), and take the Kisaku New Trail to Mount Akaiwa.

● Omote-Ginza traverse route
Nakabusa Onsen → Kassen ridge → Enzanso → Odori-no-kashira → Kiridoshi-iwa → Daitenso (Mount Otensho) → Daitensho Hütte → Mount Akaiwa → Hütte Nishidake → (on to Mount Yari via the Higashi-kama ridge). The Kisaku New Trail was opened in 1921 by the hunter Kisaku Kobayashi; Kiridoshi-iwa has chains and an iron ladder, and the ground drops away near the Kisaku relief.

● The summit of Mount Akaiwa (for experienced climbers, at your own risk)
The Omote-Ginza trail passes around the east side without crossing the summit. There is no official trail to the triangulation-point summit: it means climbing straight up a loose, crumbling slope from the southeast, with about 10 m of creeping-pine scrambling just below the top. The risk of rockfall and slips is high; stay away in bad weather.

Standard trail times for the main sections (summer / snow-free guide)

• Nakabusa Onsen → Kassen ridge → Enzanso: approx. 5 hours (ascent, elevation gain approx. 1,250 m)
• Enzanso → Odori-no-kashira → Daitenso (Mount Otensho): approx. 3 hours
• Daitenso → Daitensho Hütte → Mount Akaiwa → Hütte Nishidake: approx. 2 h 30 min

The view
From the ridge around Mount Akaiwa, the sharp rock spires of Mount Yari and the Hotaka range loom close at hand, with Mount Tsubakuro and Mount Otensho and the Tateyama and Ushiro-Tateyama ranges in view. Because the trail bypasses the summit, few hikers stand on top and you can enjoy the grand panorama in quiet.

Recommended plan (2 nights / 3 days, Omote-Ginza traverse)

• Day 1: Hotaka Station → Nakabusa Onsen → Kassen ridge → Enzanso (overnight)
• Day 2: Enzanso → Mount Otensho → Mount Akaiwa → Hütte Nishidake or Daitensho Hütte (overnight)
• Day 3: Descend the way you came to Nakabusa Onsen, or traverse via the Higashi-kama ridge to Mount Yari and Kamikochi

One or two nights on the mountain are assumed; a day trip is impossible.

5. Huts and emergency contacts

Omote-Ginza huts (all require reservation)

• Enzanso (just below Mount Tsubakuro): the base at the start of the Omote-Ginza. Reservations 0263-32-1535
• Daitenso / Daitensho Hütte (below Mount Otensho / on the ridge): the nearest lodging to Mount Akaiwa. Reservations 0263-83-5810
• Hütte Nishidake (below Mount Nishi): a base on the Mount Yari side of Mount Akaiwa, with an adjoining tent site.

There are almost no water sources on the ridge; buy drinking water at the huts. Confirm 2026 opening periods and reservation methods with each official source.

Emergency contacts

• Nagano Pref. Police, mountain rescue / Omachi Police Station: 0261-22-0110
• Azumino City Office: 0263-71-2000
• In an accident or distress: 110 (police) / 119 (fire & rescue). Always file a climbing plan.

Photo by Alpsdake