Kamikochi is a valley at 1,500 m in the Hida range, the northern of the three ranges that together are called the Japan Alps. The Azusa River runs through it, so clear that trout are visible from the bank, and the peaks above it rise steeply to more than 3,000 m. Private cars have been banned from the valley since 1975, and the road is closed completely from mid-November until mid-April. For most Japanese hikers, Kamikochi is where mountaineering begins, and the traverse from Yarigatake to the Hotaka peaks that starts here is the most celebrated high route in the country.
We walked the traverse in early September over four days. What follows is a description of the route, the terrain and the timing, written for trekkers who know the Alps of Europe or the Himalaya but have not yet walked in Japan.
The valley and its approach
Kamikochi is reached by bus from the towns of Matsumoto on the east side or Takayama on the west. The valley floor is flat, and the first hours of any trek here are a gentle walk along the river past the Kappa Bridge, a wooden suspension bridge that has become the symbol of the place, and then upstream through larch and birch forest. From the bus terminal it is about 11 km to Yokoo, where the trail splits: one branch continues up the Yarisawa valley toward Yarigatake, the other turns into the Karasawa cirque under the Hotaka peaks.
This long, easy approach is a feature of the Japan Alps that surprises many visitors. The valley path is wide and almost level, and several mountain huts along it serve as staging points. It is also where the crowds are. On weekends in high season the path to Yokoo is busy, but the numbers thin dramatically once the climbing starts.
Yarigatake, the spear
Yarigatake, at 3,180 m, is the fifth highest peak in Japan and the most recognisable, a sharp pyramid of rock whose name simply means “spear peak”. From Yokoo the trail climbs the Yarisawa valley over about 9 km and 1,500 m of ascent, passing the treeline at roughly 2,400 m and entering a broad boulder-strewn bowl with the summit visible ahead for most of the way. The gradient is steady rather than severe, and most parties reach the col below the summit in six to eight hours from Kamikochi, or split the day with a night at Yokoo.
The final 100 m to the summit is a scramble on fixed chains and steel ladders. It is not difficult in dry conditions, but it is exposed, and in the busy season there is a system of separate ascent and descent lines to avoid congestion. From the top the whole traverse is laid out to the south: a jagged ridge of rock towers leading to the Hotaka massif, with the deep notch of the Daikiretto in between.
The Daikiretto and the ridge to Hotaka
The section from Yarigatake to Okuhotaka is what gives the traverse its reputation. The ridge runs over Obami-dake, Nakadake and Minamidake, each just above 3,000 m, on a path that is rocky but straightforward. Then, between Minamidake at 3,033 m and Kita-Hotaka at 3,106 m, the crest drops into the Daikiretto, the “great cut”, a notch about 300 m deep whose sides are steep rock steps equipped with chains, ladders and painted markers.
The Daikiretto is not a climb in the technical sense, and it is passed every day in season by hikers without ropes. But it demands steady footing, good weather and a calm head. The rock is exposed on both sides, and the crux sections are narrow ledges with long drops. Accidents happen most often when the rock is wet or when people rush. We allowed about three hours from Minamidake to Kita-Hotaka and were glad of every minute.
Beyond Kita-Hotaka the ridge continues to Karasawa-dake and then to Okuhotaka at 3,190 m, the third highest summit in Japan. This stretch is still airy, with a series of chained steps, but it feels less committing than the Daikiretto. From the summit of Okuhotaka a well-worn path descends to a col and a hut at about 2,980 m, and from there a steep, zigzagging route drops into the Karasawa cirque.
Karasawa and the way down
The Karasawa cirque at around 2,300 m is one of the most beautiful campsites in Japan, a glacial bowl ringed by the Hotaka peaks and filled in late September and early October with the red and yellow of turning rowan and birch. Snow patches often survive here well into summer. From Karasawa the descent to Yokoo is about 6 km, and from Yokoo it is the same 11 km valley walk back to the Kamikochi bus terminal. Most parties finish the traverse in three to four days, with nights near Yarigatake, near Okuhotaka and, if time allows, in Karasawa.
Timing, weather and altitude
The window for the traverse is short. The rainy season usually lifts in mid-July, and snow can linger on the high ridge until then. The best conditions are typically from late July to early October, with August the busiest and most stable month. By mid-October the first snow arrives on the ridge, and after that the route becomes a winter climb requiring ice equipment. The huts close in stages through October and November.
Weather is the real hazard. The Japan Alps sit between the Sea of Japan and the Pacific, and afternoon cloud, sudden thunderstorms and strong winds are all common. Typhoons in August and September can bring several days of heavy rain and make the Daikiretto impassable. A flexible plan with a spare day is worth more than any single piece of equipment. At 3,000 m the altitude is noticeable for those arriving from sea level, and we found the approach day through the valley useful for settling in before the long climb.
Huts, camping and etiquette
The Japanese mountain hut system is what makes a traverse like this practical without heavy loads. Huts on the ridge provide dormitory beds, meals and water, and most have adjacent tent sites for a fee. Reservations are expected, especially in August and on holiday weekends, and space is tight. Water on the ridge itself is scarce, so buying it at huts is normal practice. Rubbish is carried out, and there is a strong culture of leaving no trace and greeting other hikers on the trail.
No permit is required for the traverse, but hikers are asked to submit a climbing plan at the trailhead, either on paper or online, so that rescue services know where to look if something goes wrong. Helmets are recommended for the Daikiretto and are increasingly common. Above all, this is a route to walk in good conditions. On a clear day it is one of the finest ridge walks in Asia; in cloud and rain, it is somewhere to wait.