Akaishi-dake (赤石岳, 3,121 m) is one of the high peaks at the core of the Southern Alps, and the mountain that gave the range its formal Japanese name — the Akaishi Range (赤石山脈). Its name, "Red Stone," comes from the red radiolarian chert (赤色チャート) exposed near the summit and in the Akaishi-sawa valley below — a sedimentary rock formed from hardened radiolarian ooze. The summit carries a first-order triangulation point at 3,120.53 m, the highest such marker in Japan. Together with neighbouring Arakawa-dake (荒川岳 / Warusawa-dake) and Hijiri-dake (聖岳), Akaishi-dake forms some of the most remote multi-day hiking terrain in the country, with no shortcut access to the trailheads. Summit views encompass the Southern Alps spine from Kita-dake in the north toward Tekari-dake in the south, with Mt Fuji and the Central and North Alps beyond.
Why Fukada Chose Akaishi-dake
Kyuya Fukada included Akaishi-dake in Nihon Hyakumeizan. The book lists peaks in geographical order from north to south rather than ranking them, so its position (between Warusawa-dake and Hijiri-dake) reflects location, not standing.
One image that has long circulated from Fukada's writing on this mountain is a winter view from the coast: on a clear February day he travelled to Shizuoka and looked out from the shore at the distant Southern Alps, where the great peaks — Hijiri, Akaishi, Arakawa, Warusawa — shone pure white against the sky. The mountain is also notable as the one whose name was borrowed for the entire range.
The Mountain
| Item | Detail |
|---|---|
| Elevation | 3,121 m (precise: 3,120.53 m) |
| Triangulation point | First-order marker — the highest in Japan |
| Prefectures | Shizuoka / Nagano |
| Range | Akaishi (Southern Alps) |
| Geology | Red radiolarian chert (赤色チャート) — source of the "red stone" name |
| Hyakumeizan | One of Fukada's 100 (Southern Alps section) |
| Typical season | Late June – October (multi-day approach) |
The Routes
Standard Route: Sawarajima → Akaishi-goya → Akaishi-dake (2–3 days)
Grade: Strenuous (multi-day)
The standard Shizuoka-side approach. From Sawarajima (椹島, a base at about 1,100 m on the upper Oi River, reached by company shuttle bus), the trail climbs steeply to Akaishi-goya, then continues to the summit.
Day 1: Sawarajima → Akaishi-goya (赤石小屋, ~5 hours) Day 2: Akaishi-goya → Akaishi-dake summit → return to Akaishi-goya or descend (8–9 hours round trip) Day 3: Descend to Sawarajima
Arakawa Sanzan Traverse: Sawarajima → Senmai-goya → Arakawa Sanzan → Akaishi-dake (3–4 days)
Grade: Strenuous (multi-day, exposed ridges)
The classic high traverse. From Sawarajima, climb to Senmai-goya (千枚小屋), traverse Senmai-dake → Warusawa-dake (悪沢岳 / Higashi-dake) → Arakawa Naka-dake → Arakawa Mae-dake, then drop toward Arakawa-goya before climbing Akaishi-dake. The Arakawa Sanzan (荒川三山) are Mae-dake, Naka-dake and Warusawa-dake (also called Higashi-dake). Often combined with a descent via Akaishi-goya for a grand circuit.
Akaishi → Hijiri Southern Traverse (3–5 days)
Grade: Strenuous / Technical sections
South from Akaishi-dake the ridge drops past Hyakken-daira to Hyakkendō-yama-no-ie (百間洞山の家), then over the smaller intervening peaks and Usagi-dake (兎岳) to Hijiri-dake. This is the wild, deep section of the Southern Alps, with long days between huts.
Getting There
From Shizuoka:
JR Tōkaidō Shinkansen to Shizuoka Station, then the Shizutetsu Just Line "Southern Alps" bus to Hatanagi Dai-ichi Dam (畑薙第一ダム, around 3.5 hours). This bus runs in summer only, once a day each way, by full reservation (in 2025 it operated roughly mid-July to mid-August, departing Shizuoka Station around 10:00 and reaching Hatanagi early afternoon).
From the Hatanagi summer parking area, the Tokushu Tokai Forest shuttle bus runs free, round-trip, to Sawarajima (about a 1-hour-10-minute ride). It is available only to guests staying at least one night at one of the company's huts — Sawarajima Lodge, Senmai-goya, Akaishi-goya, Arakawa-goya, Hyakkendō-yama-no-ie, or the Akaishi-dake emergency hut. Hikers planning to camp only cannot ride; they must walk roughly 20 km (about 5 hours) from the Hatanagi Dam area instead.
From Nagano (less common):
Via Iida or Ōshika village toward the Shiomi side, joining the main ridge and traversing south. Mostly used for full-range traverses.
There is no railway line that reaches the trailheads, and no ropeway exists.
Mountain Huts
Akaishi-goya (赤石小屋): Staffed Tokai Forest hut on the standard route. Advance booking required.
Akaishi-dake Hinan-goya (赤石岳避難小屋): At about 3,100 m, this is the highest emergency hut in Japan after Mt Fuji. Despite the "hinan-goya" (emergency hut) name, it has a resident manager in summer and operates as a basic lodge. Stays are self-catering — retort meals and cup noodles are sold, but there is no full meal service. Confirm operating status before relying on it.
Hyakkendō-yama-no-ie (百間洞山の家): Staffed hut on the Akaishi → Hijiri traverse, south of the summit. A key hub for the deep Southern Alps southern traverse. Advance booking essential.
Senmai-goya / Arakawa-goya: Used on the Arakawa Sanzan traverse approach.
Flora and Wildlife
Asiatic black bears (ツキノワグマ): This is the bear species present in the Southern Alps approach valleys — not the brown bear of Hokkaido. A bear bell is sensible on lower forest sections.
Japanese rock ptarmigan (ライチョウ): Found on the upper rocky and pine-scrub ridges. The Southern Alps is one of the documented strongholds for this alpine bird.
Alpine flora: Komakusa (駒草) appears on alpine sandy ridges; Shinano-kinbai, Hakusan-ichige, and Chinguruma fill the snowmelt slopes in July–August, where flower meadows spread across the alpine zone.
Red rock geology: The red radiolarian chert that gives the mountain its name is exposed near the summit and in the Akaishi-sawa valley, showing distinctive red and orange hues. Some accounts note that the colour can be heightened by low-angle morning light.
Seasonal Guide
Late June – early July: Season opens with deep snow on high passes and steep snowfields. Experienced parties only.
Mid-July – August: Main traverse season. Huts busy; book 2–3 months in advance.
September: Often the best month — clearest views, fewer hikers, more stable weather windows.
October: Late season; first snow likely. Huts begin closing mid-month.
Practical Tips for Foreign Visitors
Commitment required: The Southern Alps core (Akaishi-dake, Arakawa-dake, Hijiri-dake) is among Japan's most remote mountain hiking terrain. There are no ropeways and no short-cut access. Plan for 3–5 days minimum, carry a food margin, and confirm all hut bookings in advance. This is serious wilderness travel.
Tokai Forest shuttle: Access to Sawarajima by the reserved shuttle is only possible for guests of Tokai Forest huts. There is no public access to the trailhead by this bus — book a hut first, then the shuttle. Tent-only hikers must walk in from the Hatanagi Dam area.
Reservations and language: The summer Shizutetsu bus and the hut-linked shuttle both require advance reservation, and booking systems are mostly in Japanese. Arrange transport and huts well ahead, and build buffer days into your plan in case of weather.
Southern Alps grand traverse: The full north-to-south traverse linking Kita-dake, Ainodake, Shiomi-dake, Arakawa-dake, Akaishi-dake, Hijiri-dake and Tekari-dake over many days is one of the great challenges of Japanese mountaineering. Most hikers break it into separate trips.
Frequently Asked Questions
Is Akaishi-dake a day hike or an overnight trip?
It is a multi-day mountain, not a day hike. Plan for 3–5 days minimum: the standard Sawarajima route takes 2–3 days, the Arakawa Sanzan traverse 3–4 days, and the Akaishi → Hijiri southern traverse 3–5 days.
Can I reach the trailhead without a car?
Yes, but it takes time and reservations. From Shizuoka Station the summer-only Shizutetsu "Southern Alps" bus runs once a day each way to Hatanagi Dai-ichi Dam (around 3.5 hours), and from there the free Tokai Forest shuttle bus carries hut guests to Sawarajima (about a 1-hour-10-minute ride). There is no railway line or ropeway to the trailheads.
Do I need to book the huts in advance?
Yes. Akaishi-goya, Hyakkendō-yama-no-ie and the other staffed huts all require advance booking, and the Tokai Forest shuttle to Sawarajima is available only to guests staying at least one night at a company hut. Booking systems are mostly in Japanese, so arrange transport and huts well ahead.
When is the best time to climb?
September is often the best month, with the clearest views, fewer hikers and more stable weather windows. The general season runs late June to October; mid-July to August is the busy main traverse season, while late June to early July still holds deep snow on high passes and is for experienced parties only.
Are there bears, and what should I carry?
The bears here are Asiatic black bears (ツキノワグマ), not the brown bear of Hokkaido. A bear bell is sensible on the lower forest sections; bear spray is not the standard precaution for this region.
This guide is part of the Japan's 100 Famous Mountains: Complete Hyakumeizan Guide series.
