I wouldn't say it is unrealistic, but given that in the past you've voiced uncertainty about winter mountain walking, I would say that you might want to make sure you are ready for snow walking and very cold temperatures. In May it is definitely not a beginner winter walker's walk. You might have to deal with using crampons and possibly an ice axe and you might want to be familiar with avalanche lore. Spring is the most dangerous time to be walking in alpine conditions due to loose snow from the alternating heating and cooling of the day/night cycles. You will have to carry more weight than your summer walks to protect against the cold, plus it would be a good idea to bring along some kind of shelter just in case. I would also caution against doing this walk alone at this time of year; this is the period when most people die in the mountains because of insufficient preparation and very few people on the trails to help you when you get in trouble.

I've walked Oku-Shirane two times, both in summer. I very strongly suggest that you don't tackle the mountain from the Nikko side. The trail is very old and badly maintained and the first time I went the entire eastern slope was one big mass of loose rock slide. It was really scary climbing. The entire time I met only one other person... probably because most people had probably read information somewhere warning about the conditions of the east flank... and that person turned back about half way. The advantage of the east side is that buses run all year long, but I'm not sure that you can access the safer west side (from Oze) at this time of year. I don't know if there are any buses running until the end of June.

Sorry if I sound so cautious about this mountain, but I had difficulty in August, so I imagine that May will be quite a lot more dangerous. I'm concerned about your safety, especially if you don't have much winter mountaineering experience. If you can go with an experineced winter walker then go for it, but I really don't recommend this if you don't have the experience and you want to try it alone.

Also this year has been particularly cold, with snow still lingering in the very low mountains around Takao... something really really unusual. I would think that conditions up in Shiranesan are quite a bit more severe.

If you do decide to go please be careful. I wouldn't want the bears to lose their number one advocate!

p.s. If you really want to do some alpine walking with conditions similar to Oku-Shirane, why don't you give Kita-Yatsugatake a try? The trails are well maintained, there are year-long active mountain huts at reasonable distances, there are quite a few people, (many very experienced) on the trails, everything is quite accessible by bus (even in winter), there are quite a few escape routes along all the trails, and the whole place is well set up for year-long walking. For a beginner I would say that it is much safer and much more accessible (plus, if you reserve early, you can even get a private room for yourself at the Mugikusa Mountain Hut).

Just a thought.

Thanks for this Butuki. I didn't know it was better to approach Shiranesan from the Oze side. When you climbed it, did you set off from Yumoto or did you get a taxi from Yumoto to the trailhead? Alternatively, did you use the cable car? There's also apparently a route from the cable car. If you did use that route, did you take a bus there (where?) from Nikko. Shiranesan is very tempting to me because I love Nikko/Yumoto. I might go have a look and see what it's like and turn back if things look like they're getting hectic.

One more question. Is Kita-Yatsugatake a no-go in Golden Week. Two actually. Can you camp up there and if so would it be absolutely freezing around Golden Week? I'm really keen on avoiding the huts as much as possible this year, even if they have private rooms!

Thanks again Butuki.

I camped at Yumoto and just walked to the trailhead from there (the whole approach was closed to car traffic... the approach took about an hour (?)). Camping at Yumoto was actually quite nice, but I'm not sure if it is open at this time of year (you have to pay to stay at the hotel next to the campsite).

I didn't know about the cable car approach. Don't you think it would be closed at this time of year? When exactly does the alpine flower viewing season start up there?

I don't think you have to worry about crowds in Yatsugatake. Even in the summer it is never so crowded that you can't enjoy the trails. At this time of year it is still so cold that most people wouldn't even think of going. Camping can be done anywhere, even wild along the trails (one of the mountain hut people told me that quite a few foreigners seem to do this) and almost all the huts have camping areas. People camp there in the winter, too, so the huts are prepared for that. As to temperatures... this time of year above 1500 meters anywhere is going to be freezing. Prepare to do winter style walking. Bring your crampons.

I think a lot of hikers have a misconception about mountain walking in spring... because things are getting warmer down below. Above treeline spring is actually just as cold as winter and a lot more dangerous than winter due to very variable conditions. You can get blizzards and the snow conditions... ie. rotting snow fields... can be very bad, with iced over snow surfaces caused by melting snow during the day and freezing at night. It isn't really until June that you can expect things to warm up and the trail footing to be safe.

For Yatsugatake, for some reason the snow tends to accumulate less than on the surrounding mountain ranges. Yatsugatake is a very "dry" mountain range, so even in winter you can often climb the highest peaks without too much technical equipment. I think if you have the proper winter tent and sleeping bag, though, you shouldn't have too much trouble with the camping aspect. Just make sure you carry a piss bottle for the night when you don't want to exit the tent and small water bottles that you can use to keep your drinking water warm inside your jacket and sleeping bag where they won't freeze. Also keep your boots inside your sleeping bag at night so they don't freeze, too. If you don't have a winter sleeping bag you can use your insulating jacket on top of you with a surrounding bivy sack. Also, you might want to use a white gas stove rather than a cannister stove... sometimes cannister stoves have problems in the cold.

I'm making it sound like dire news! I've been in Yatsugatake in winter and camped there. It wasn't quite as bad as I had imagined before I went. And you can always escape to the mountain huts nearby.

Looked into it a bit more last night Butuki. Apparently most people do tend to approach Shiranesan from the Gunma end these days, starting from a place called Sekinuma (I think, not sure of the reading of the kanji). It's possible to get there from Yumoto through a tunnel-road that is only open sometimes (all sounds very familiar, right?). There's also a campsite at the start of the trail at that side, and it looks like it might be open year-round. I think I'll camp there, approach from that side and come down into Yumoto.

The cable car is apparently running in April and May, but it looks like it doesn't start until quite late in the morning, so I'll give that a miss.

Cheers for the info about Yasugatake too. Will definitely head that way fairly soon. Willing to give winter camping a shot once, despite the fairly grim picture you paint, because as I said I really don't want to be in those huts this year.

Thanks again for the info.

Well, I sure hope that Shiranesan lets you do your walk without problems. That would be great. I only brought up the grim side of things because it needed pointing out. We may have joked about those 40 people getting lost in Akita the other day, but they were experienced winter walkers and still they got into trouble... and that was only two weeks ago. So please do be careful. And have a good time!

Cheers. I'm taking the advice very seriously and know all about the weather and avalanche dangers, so I'd say there's every chance I won't push on to the top this time round. Having said that, it'll be nice to have a little look and I'll use any excuse to get back up to Nikko! Also, I've been finding this account (Japanese) fairly inspiring.

Hey, thanks for the link to the Shiranesan walk. I love to get any new info on mountain walks whenever I can, so this is really helpful.

Looking at the map I might want to suggest that when you reach the ring trail going around Goironuma instead of keeping to the west ridge overlooking the pond that you try the east ridge overlooking the pond (via Goiroyama). The west ridge is higher but the east ridge has a much better view of the whole vale. It's a really cool place. I couldn't stop taking photos when I reached this area.

I always wondered where the bus from the north came in. Now it all makes sense.