Mt. Akasawayama

Mt. Akasawayama (2,670.5 m) stands on the border of Matsumoto City and Azumino City in Nagano Prefecture and is one of Japan’s 100 Highest Mountains.
In the southern Northern Alps, it is a peak branching south from the Nishidake area on the Higashikama Ridge that runs east from Mt. Yarigatake, set just off the Omote-Ginza traverse route. There is no general trail; it is a route for experienced climbers who reach it by route-finding from the Hutte Nishidake, and few people stand on its summit.
For public transport, you reach the base, the Hutte Nishidake, by following the Omote-Ginza (Nakabusa Onsen → Mt. Tsubakurodake → Mt. Otenshodake → Nishidake), and you reach Nakabusa Onsen by a scheduled bus from JR Hotaka Station.

Mt. Akasawayama is not climbed on its own; it is a peak for advanced climbers, reached as an out-and-back from the Hutte Nishidake after traversing the Omote-Ginza. The classic itinerary is the Omote-Ginza traverse Nakabusa Onsen → Mt. Tsubakurodake → Mt. Otenshodake → Hutte Nishidake (overnight), with the hut about 2–3 days in. You reach Mt. Akasawayama by descending the gap (a steep, cut-away saddle) beyond the Hutte Nishidake tent site and returning; there is no general trail or signage, the terrain is steep, and route-finding with appropriate skill and experience is required. You can also enter via the Yarisawa valley (Kamikochi → Yokoo → Yarisawa → Mizumata-norikoshi → Higashikama Ridge → Nishidake).
The Hutte Nishidake is the base for lodging and emergencies. The Hutte Nishidake (run by the Enzanso group) usually operates from early July to early October and is fully reservation-based, with a small tent site. The climbing season is early July to mid-September, while the hut operates; outside that period snow and ice make the route unsuitable for general hikers. Even in the snow-free season Mt. Akasawayama is not a peak for general hikers, so plan carefully.

*Information last checked: June 14, 2026

How to access the trailhead

1. [Outbound] Hotaka Station → Nakabusa Onsen (start of the Omote-Ginza)
2. [Outbound] Takebashi Station → Nakabusa Onsen (overnight bus)
3. [Return] Nakabusa Onsen → Hotaka Station
4. [Return] Nakabusa Onsen → Shinjuku Station (overnight bus)

1. [Outbound] Hotaka Station → Nakabusa Onsen (start of the Omote-Ginza)

From in front of Hotaka Station on the JR Oito Line, take the “Nakabusa Onsen scheduled bus” run by Nan-an Taxi and get off at Nakabusa Onsen, the start of the Omote-Ginza traverse (the Tsubakurodake trailhead).

Ride time: 55 minutes
Fare: 1,500 yen for adults
Operating period: selected days, roughly late April to early November

There are three operating patterns — Pattern A, Pattern B, and Pattern C — with different numbers of buses. Pattern A days have six buses including the early 5:15; Pattern B days have five (the early 5:15 is suspended); Pattern C days have no morning buses, with the first bus at 11:10 and only three buses. On the busiest days (marked on the operating calendar) Pattern A adds an extra 4:30 departure. Always confirm which pattern applies on your date on the official Nan-an Taxi operating calendar.

Bus TimetableHotaka Station to Nakabusa Onsen (Pattern A)

Bus TimetableHotaka Station to Nakabusa Onsen (Pattern B)

Bus TimetableHotaka Station to Nakabusa Onsen (Pattern C)

Reference: Nan-an Taxi – Nakabusa Onsen scheduled bus (operating calendar)

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

Take the Mainichi Alpen-go “Tsubakuro / Jonen / Cho” overnight bus from Takebashi Station on the Tokyo Metro Tozai Line and get off at the Tsubakurodake trailhead, Nakabusa Onsen. Reservation is required.

Takebashi Station (Tozai Line): assemble 22:45, depart 23:00 (Mainichi Shimbun west-entrance lobby)
Tsubakurodake trailhead / Nakabusa Onsen: arrives around 5:30–6:00

Ride time: about 6–7 hours (overnight)
Fare: 8,800–13,800 yen (varies by season and seat; reservation required)

Details: Mainichi Alpen-go climbing bus, Tsubakuro / Jonen / Cho

3. [Return] Nakabusa Onsen → Hotaka Station

After your descent, take the “Hotaka Station scheduled bus” run by Nan-an Taxi from Nakabusa Onsen and get off at Hotaka Station.

Ride time: 55 minutes
Fare: 1,500 yen for adults
Operating period: selected days, roughly late April to early November

The downhill buses also vary by pattern. Pattern A and B days have five buses; on Pattern C days the two morning buses (9:00 and 10:45) are suspended, leaving three.

Bus TimetableNakabusa Onsen to Hotaka Station (Patterns A and B)

Bus TimetableNakabusa Onsen to Hotaka Station (Pattern C)

Reference: Nan-an Taxi – Nakabusa Onsen scheduled bus (operating calendar)

4. [Return] Nakabusa Onsen → Shinjuku Station (overnight bus)

From Nakabusa Onsen, take the Mainichi Alpen-go “Tsubakuro / Jonen / Cho” bus to the terminus, Shinjuku Station West Exit. Reservation is required.

Nakabusa Onsen: departs 12:45 or 13:45 (varies by date; check the linked page)
Shinjuku Station West Exit: arrives around 18:00–19:00

Ride time: about 5–6 hours
Fare: 8,800–13,800 yen (varies by season and seat; reservation required)

Details: Mainichi Alpen-go climbing bus, Tsubakuro / Jonen / Cho

Climbing route and safety notes

Route: Nakabusa Onsen (Tsubakurodake trailhead) → Kassen Ridge → Enzanso → Mt. Otenshodake → Hutte Nishidake (overnight) → Mt. Akasawayama (out-and-back). The Hutte Nishidake is reached by the general Omote-Ginza traverse over 2–3 days; the total climbing time is long and it is an advanced route that requires at least one overnight. You reach Mt. Akasawayama by descending the gap beyond the Hutte Nishidake tent site, but you can also enter the Hutte Nishidake from Kamikochi via the Yarisawa valley and the Higashikama Ridge.

Off-trail notes: Mt. Akasawayama has no general trail or signage, and the gap descent and steep terrain require route-finding and an experienced climber’s skill. Do not rely on fixed gear; carry a map, compass, and GPS, and stay out if you lack experience. The Omote-Ginza ridge is above the tree line, so watch for strong wind, lightning, and sudden weather changes.

Water, huts, season: There is no water source on the ridge, so buy drinking water at the Hutte Nishidake. The Hutte Nishidake (run by the Enzanso group) usually operates from early July to early October and is fully reservation-based, with a small tent site. The climbing season is early July to mid-September; outside that period snow and ice make the route unsuitable for general hikers.
― Hutte Nishidake direct line 090-7172-2062 / Enzanso office 0263-32-1535

Gear and emergencies: Carry warm layers, rain gear, a helmet, a headlamp, a map/GPS, and plenty of water and food. In an emergency call 110 (police) or 119 (fire/rescue).
・Azumino Police Station 0263-72-0110

Photo by Alpsdake / Wikimedia Commons, Public domain