[Northern Alps] Mt. Kasumizawa West Ridge | Steep ascent requiring an ice axe and superb views of the Hotaka mountain range

I love the time spent walking along quiet ridgelines.

The route I walked this time was the
Northern Alps Mt. Kasumizawa West Ridge route.

There is a laughably steep ascent right from the trailhead.
In some places, I had to climb step by step while driving my ice axe into the snow surface.

What awaited me after crossing the treeline was
a grand view of the Hotaka mountain range spreading out before my eyes.

It was a mountain trip where I encountered scenery unique to winter.

Introduction

Mt. Kasumizawa is a mountain in the Northern Alps located to the west of Kamikochi.

Generally, the route from Tokugo Pass is well-known, but
the one I walked this time was the winter-only West Ridge route.

Although it is a variation route with continuous steep ascents,
a view of the Hotaka mountain range unfolds directly in front of you from the summit.

In this article,

・Route conditions of the Mt. Kasumizawa West Ridge
・The state of the steep winter ascent sections
・Views from the summit

I have summarized the above.

I hope this will be helpful for those considering Mt. Kasumizawa in winter.

Mountain Trip Overview

Mountain Name: Mt. Kasumizawa
Mountain Area: Northern Alps (Kamikochi area)
Date: March 14, 2026
Weather: Sunny

Course:
Sakamaki Onsen → Kama Tunnel → Mt. Kasumizawa West Ridge → Mt. Kasumizawa → Round trip

Distance: 13.6km
Cumulative Elevation: +1,581m / -1,581m
Activity Time: Approx. 9 hours

Physical Difficulty: ★★★★☆
(For experienced winter mountaineers due to the long, steep ascent)

Overall Course Map

Starting from Sakamaki Onsen, I passed through the Kama Tunnel to reach the West Ridge.
I hiked the same route round-trip.

Reasons for choosing this mountain

・The forecast promised good weather
・I had wanted to hike the Mt. Kasumizawa West Ridge for a long time
・I was drawn to this winter-only route
・Recent records suggested there would be a trail to follow
・The view of the Hotaka mountain range directly from the summit

To the trailhead

This time, I started from Sakamaki Onsen.

I set off early in the morning while it was still dark.

I walked along the road for a while, then crossed the winter gate to head toward the Kama Tunnel.

Caution is required until reaching the Kama Tunnel due to vehicle traffic, but from the tunnel onwards, it is a winter-closed section and becomes a quiet path.

When I emerged from the tunnel, the blue sky spread out, and I felt, "It's going to be a good day."

Start of the climb

Upon arriving at the trailhead, I put on my helmet, crampons, and ice axe.

And as I began to climb...

It was an immediate steep ascent.

The incline was so steep it made me laugh.

I thought it was just a short section to the first ridge, but in reality, the steep climb continued beyond that.

As the snow deepened, there were places where I had to climb on all fours.

Middle section: The steep climb of the West Ridge

The defining feature of the West Ridge is the constant, steep incline.

In areas with a steep incline, there were times when I had to
plant my ice axe into the snow to support my body while climbing.

The difficulty level seems to change significantly depending on the snow conditions.

Even so, when the view opened up from time to time,
distant mountains began to appear, raising my expectations.

Along the way, I could also see Taisho Pond.

There were also sections with fluffy snow,
making my steps feel lighter.

Still, it was basically a steep climb.
The ascent continued to be demanding, requiring constant focus.

The timberline and the Hotaka mountain range

As I approached the timberline,
my anticipation for the scenery grew.

And then, as I emerged from the forest zone—

The Hotaka mountain range appeared right before my eyes.

It was a view that made me stop in my tracks.

Looking back,
Mt. Norikura, which I had been looking up at before starting the climb,
was now visible at almost eye level.

Rock walls and narrow ridges

A part of this route that made me a bit nervous was
the rock wall near the timberline.

There was an old fixed rope that proved helpful.

After crossing the rock wall,
I encountered a narrow ridge.

Since the steps were small, I crossed it with great caution.

Looking back,
I felt a bit relieved that the section was shorter than I thought.

Summit

The final stretch becomes a gentle climb,
leading to the summit of Mt. Kasumizawa.

The best view was waiting for me at the summit.

Right in front of me was the Hotaka mountain range.

In the distance is
the ridgeline from Mt. Kasagatake to Mt. Sugoroku.

Looking to the right,
the pointed Mt. Jonen and
the ridgeline from Mt. Chogatake to Mt. Otensho.

Further in the distance are

・Yatsugatake
・Southern Alps
・Central Alps

Looking back

・Mt. Norikura
・Mt. Yakedake

And beyond that,
the massive Mt. Haku stood firmly.

Time at the summit

A windless summit.

Time to eat cup noodles
in the Northern Alps all to myself.

It was a very peaceful moment.

Descent

You need to be careful on the rock walls during the descent as well.

Proceeding with caution,
I descend the steep ridge.

Once the bamboo grass appears,
the trailhead is almost here.

Passing through the Kama Tunnel,
I finished by walking along the road back to Sakamaki Onsen.

Parking Information

Sakamaki Onsen Ryokan Parking Lot

Capacity: Approx. 20 vehicles
Fee: 1,000 yen per day
Restrooms: Available

Entry/Exit: 5:00 - 19:00

I arrived around 4 o'clock on this day,
and I was about the 5th car.

There was a sign indicating the lot was full at the time of departure.

Day-trip bathing: 600 yen

It was a lovely bath with sulfurous scent and mineral deposits.

Course Conditions and Precautions

・Road walking from Sakamaki Onsen to the trailhead
・Vehicle traffic exists up to the Kama Tunnel gate
・Steep ascent immediately from the trailhead
・Ice axe essential on steep snowy slopes
・Rock walls near the timberline
・Narrow ridge after passing the rock walls

※I believe the difficulty level changes significantly depending on snow conditions

※As of March 2026

Reflections

The
Mt. Kasumizawa West Ridge route I had wanted to try.

For someone like me who isn't great with heights,
it was a course that made me hesitate a little.

If it seemed too difficult,
I had considered waiting along the way.

Even so,
thanks to my hiking partner who walked with me,

we reached the summit safely.

The view of the Hotaka mountain range directly in front of us
was something special, unique to winter.

It was a very memorable hike
where I could fully enjoy the Northern Alps.

There are several winter routes in the Northern Alps that involve climbing up steep ridges.

▶︎ Mt. Jonen East Ridge | One of the Northern Alps' premier winter ridges

▶︎ Mt. Jiigatake East Ridge | A long, steep ridge route

Conclusion

I love the time spent walking along quiet ridgelines for long periods.

Focusing on mountains in Shizuoka,
I hike every weekend.

In this NOTE,

・Hiking logs
・Mountains of Shizuoka
・Ridgeline routes for long-distance hiking

are what I mainly write about.

▶ Hiking log summary
Magazine: "One Mountain at a Time, Hiking Logs"

▶ Click here for this month's summary

If you love mountains,
I would be happy if you followed me.

See you next time with a record of another mountain.