Hakuba Yari Onsen hike (in the rain!) - Nagano, Japan

Located in the Japanese northern Alps, Hakuba is popular during the winter for its snow/winter sports and resorts. During the summer, you have the opportunity to hike! Our friends invited us to join them for a hike and overnight stay at Hakuba's Yari Onsen. 

What to know before you hike

Yari Onsen facilities

Mountain hut stay: 9500yen (+2000 to 3000yen if you want meals included)

Camping site: 2000yen + 1000yen/tent

Onsen (ala carte): 1000yen

Reservations were made for a camping spot during the preceding spring to ensure we would have a spot. We didn't end up using our reservation and was lucky that the mountain hut had openings for all 5 of us, but this was likely due to the inclement weather and reservations are highly recommended. Arrive by 15:00 for safety and pay with cash upon arrival.

Mountain hut

At the inner entrance to the mountain hut, there is a large shelving unit with provided slippers. 

Remove your hiking shoes and use the provided slippers to walk around the facility. Do not wear footwear into the hut or into the baths past the changing room. 

The main mountain hut we stayed in had about 10 different bunk areas on 2 "floors", 8 which have 4 beds each, separated with a plastic divider near the head. The remaining 2 bunk areas are for 2 people each (no plastic divider).

The provided bedding is a futon + comforter and a small rectangle cushion to serve as a pillow. I thought these were sufficiently warm and seemed clean. I considered the space per person quite adequate for a mountain hut based on what I expected from Mt Fuji, if not even a little roomy. 

Lights off is at 21:00 and expect the lights to go back on at around 04:30 in preparation for sunrise. 

I think there are also some private huts available if you're able to reserve them in time.

The bathroom is in a separate building with 3 urinals and 3 stalls and operates similarly to a port-a-potty with that same strong chemical smell. This is not like Fuji where the mountain huts often have a full toilet. It is also quite dark in there, especially at night because it doesn't have independent lighting. 

Potable water is available from a 2 faucet sink at the main building (where the staff sell items and I think distribute the mountain hut-provided meals). It doesn't have any discernible taste and does not need to be filtered out of the tap. You will see people filling up their water bottles/reservoirs and also stand near the sink to brush their teeth with this water. 

Camping sites

There are about 10+ camping sites just below the open air onsen area where hikers can set up their own tents. 

This is where we had intended to spend the night, but were intimidated by the rain and opted out for the drier, comfier and easier mountain hut option. So unfortunately I cannot speak much about this, but it did seem like it was going to be really cool - especially if the weather is clear and you have the nice view! The ground surface is small rocks, so if you do tent camp, it is recommended to bring a sleeping pad for comfort. 

Using the onsen

Since this destination is in the middle of a hike, onsen etiquette is observed but with some slight modifications for the location.

There are two onsen areas. One is the open air bath which is mixed gender and open/exposed with a great view (when not rainy and cloudy) . 

It is not uncommon for women to wear swimsuits to use this onsen during the regular hours. There is one hour every night (20:00 - 21:00) where it is for women only during which swimsuits were not worn. 

The sun will already have set for the women's only hour so it's reasonably private although hard to see and not much of a view. 

The second bath is for women only at all hours and offers privacy in exchange for the nice view. It is walled on 4 sides but has a half open roof above the bath area. 

Each bath has its own changing area with shelving to store your clothes and other personal belongings related to visiting the bath.

Bring in your towel(s) and clothes you plan to change into after the bath. (Do not bring your entire hiking backpack into the changing area.) Remove your clothes & tie up your hair (if it will touch/be in the water when you're in the bath) and leave your clothes on the changing room shelf. 

Enter the bathing area and use one of the supplied "buckets" or pans to scoop water from the bath. While crouching on an area where the poured water will disperse away from the bath, like on the far edge for the open air bath or the wooden platform in the women's only bath, dump the water over your body to "rinse off" before entering the bath. There isn't really a place to use shampoo or soap, and I think they actually ask you not do use those types of products, so the rinse before is a bit more symbolic than actually "washing".

Typical onsen use etiquette applies once you get in: do not wet/dip your hair in the water, do not put your head in the water, if you are using a modesty towel, keep it out of the water, etc. 

When you're done, simply leave the bath, go back to the changing area to dry off and get dressed and then leave the onsen area.

What to pack/bring for the hike and overnight stay

- food for day 1 lunch, dinner and day 2 breakfast & snack (unless you are planning to buy food from the mountain hut)

- at least 2L of water for one way. You can fill up at the mountain hut. 

- full change of clothes + optional lounge clothes for layering/relaxing after bath but before descending hike

- swimsuit (for women only), optional but it seemed that all women wore one in the open air bath during non-women only times

- body towel

- modesty towel (about hand towel sized)

- toothbrush/toothpaste. We purchased disposable, individually wrapped toothbrushes from a 100yen store that had the toothpaste built in and activated with water. 

- bag(s) for your trash and wet clothes/towel 

- rubber slippers if you prefer to wear your own around the onsen and mountain hut areas (esp if you are tent camping so you don't have to put back on your hiking shoes every time you want to walk somewhere since you won't have access to the ones provided by the mountain hut)

- portable charger 

- something to keep you entertained (book, deck of cards, etc) after arriving at Yari Onsen

- If you are tent camping, + tent, ground tarp, pegs, sleeping bag, sleeping pad (surface is very rocky)

- hiking sticks, highly, highly recommend at least 1 if not 2.

- backpack that fits all this stuff (we had a 24L and 30L backpack but didn't pack the stove)

- all your other typical small things just in case: bandaids, tylenol, body wipes, contact lenses, hand sanitizer, comb, hair ties, deodorant, cash, daily medications, sunscreen, hat, rain gear

Our specific (unused) tent camping items:

Marmot Ultralight 2-person tent with rain fly

Marmot 2-person tent footprint

4 tent pegs (additional to the pegs that came with the Marmot tent)

10C compact sleeping bags

offbrand foot pump inflatable sleeping pads

Our hike overview

Day 1 - The ascending hike

There are two ways to approach Yari Onsen. We used the Sarukura trail and parked in the designated parking area (approximate location can be searched in Google Maps with "猿倉登山口"). 

According to our friends who did the hike before, this parking lot can become full. If that's the case, someone will redirect you, and you will need to park all the way down the hill, closer to "Hakuba Happo Onsen Obinata no yu". It's about 5km uphill to get to the trailhead, so consider taking a taxi to get to the start if you need to park down there. 

There is a large facility and a bathroom at the beginning of the trail. We didn't go into either (opted to use the bathrooms at a conbini before the final drive up), so I'm not sure exactly what resources they have or what it looks like inside, but this is also where you could take a break, catch a taxi from or wait for a bus. 

The trail is slight mix of different surfaces and coverage for the first 3/4. There is some dirt and tree/plant cover for some areas and others is mostly small/medium broken up rocks (larger than gravel). You're traversing kind of across and up, so it's not just steep uphill slopes and sometimes you do some small downhills.

Just as our luck would have it, it started steadily raining about 30 minutes into our hike and didn't let up the whole time. While it was reasonably cool temperature-wise, it made the rock surfaces slippery and created some small and large streams of water throughout the hike, and the clouds blocked our view out entirely. Truthfully, we did consider turning back after hiking for about 90 minutes in the rain because it showed no signs of stopping, and we would have a difficult time doing our planned tent camping. But since it wasn't nearly as bad as Fuji, and there was a non-zero chance of getting into the mountain hut, we trudged onwards. 

The last bit of the hike towards Yari Onsen is almost entirely exposed and includes traversing across about 3 snow piles. As I understand it, typically you can just (carefully) walk across the snow on your own during good weather. Because of the volume of rain during our hike, there was a large steady flow of water down these areas where a wooden bridge had been set up that allow hikers to get across. They are not extremely long, and I did feel fairly safe when walking across when the water level wasn't too high. 

It does get a bit more steep at the end, and you should be able to start to smell the sulfer and see the mountain hut as you approach (during good weather). 

We took about 4.5 hours of hiking at a moderate speed with somewhat minimal breaks to get to Yari Onsen. We could have been done a little sooner, but definitely needed to be careful in the rain + the time to consider turning around lol. 

Staying at the mountain hut

We arrived at the mountain hut just after 13:00, rain still constantly pouring down, and inquired about available space in the mountain hut. We were able to get 2 bunks - 1 for three people and 1 for 2 people. This is how we were planning to split the tents anyway, so that worked fine for us. We were instructed to leave our wet clothes outside the mountain hut. There was a hanging rack already full of jackets from other hikers - we were probably amongst the last people to arrive who were intending to stay the night.

After settling into the space, we headed straight for the onsen since that was the main motivation for the hike and we were soaking wet and a bit cold anyway. The three girls opted for the enclosed women's only bath. The guys didn't really have a choice - open air bath in the rain for them. 

The mountain hut had full size umbrellas available to borrow for staying dry between the buildings. We also saw people using them inside the onsen, but the rain did help provide a cooling effect in contrast with the hot bath water.

After we had all warmed up and dried off, we all met back up at the mountain hut and just relaxed and played cards for a bit before taking a nap/resting. One of the girls went for another bath on her own while we were sleeping (she ended up being the only one in there - super relaxing!). 

I woke up around 19:00 and waited around for a bit because I wanted to use the open air onsen during the women's only time (20:00 - 21:00). The rain had just stopped a little before and it was still cloudy, but much nicer to be outside. 

We used the changing area attached to the main bath and didn't bother with swim suits for this since it's quite dark and women only anyway. I thought it might be a little busy based on how many people were moving around at 20:00, but there were only 2 other women in the bath and we were the only two for a bit more after they left. The water in the main bath is definitely hotter than the women's only bath and it's certainly different to be out in the open mountain air! We stayed for only about 20 minutes before heading back to meet the guys for dinner. 

M had brought a burner and a little pot for boiling water, so the guys had prepped our freeze dried meals on the bench outside the main building during our bath. 

We were still eating outside when it was time for lights out (21:00) at which time, all lights really went out lol. We already had our headlamps, but since we had the only lights, it attracted ALL THE BUGS so it was a hassle to walk, eat, talk or drink without a bug banging into your face. This is probably why there was so much movement from the other hikers at 20:00 - they were preparing for lights out. 

Lesson learned for sure. We cleaned up, brushed our teeth and settled in for bed around 21:30.

Day 2 - The descending hike

Not having any particular deadline we were trying to reach, we didn't have a specific time we were planning to leave. I slept a bit intermittently, so I easily woke up when other hikers in the mountain hut started moving around and the internal lights turned on at 04:30, ahead of sunrise. I wandered outside to no rain but still quite a bit of clouds, so no epic sunrise view for us lol. 

As the sun continued to rise, things did seem a little nicer than they were the previous day, and we were still happy to see everything in the light!

The girls opted for one last dip in the main bath (with swimsuits) before final pack up and checking out. 

We were one of the last at the mountain hut and finally departed just after 07:00. (Most other hikers seem to have left closer to 05:00 or 05:30 and some continued on different routes.) Apparently the descending trail had been closed temporarily overnight because one of the bridges had either washed away or was too dangerous to traverse(?) but it had opened back up by the time we wanted to leave.

Since it wasn't raining, we knew we wanted to get out while the weather was still clear but also take the pictures we didn't really have the opportunity to stop for the previous day.

And although there wasn't any active rain, there was still plenty of water running downhill, with even more volume and speed in some areas than the previous day. 

At one of the little bridges, there was so much water running down that it was spilling over the top of the walkway and was over ankle deep. It was running quite quickly too and was a bit intimidating tbh. My husband had been a few minutes ahead of the group and had crossed already. We decided to take off our shoes and socks to cross to keep them dry for at least a little longer.

And then back to normal hiking!

We made it back down in just about 4 hours, ending just after 11:00. Not too shabby and luckily the weather held up for the entire hike back! It was overcast and somewhat cool-ish but not raining. Still didn't get the $100 views because of the clouds, but it definitely could have been worse.

I can't believe it rained on another hike, especially for the intensity and duration that it did, but it definitely makes the experience memorable. We were all sad that we didn't end up doing the tent camping because of that, but all agreed that the mountain hut was the safer choice with so much less hassle when dealing with the rain and wetness. 

I never would have thought I'd do a hike and overnight stay in the mountains with an onsen kicker, and I'm so glad to have opportunities like this and friends to do it with!