Every spring around this time the road up from Norikura Kogen (sorry it’s only in Japanese) to Mt. Norikura opens up with bus service to Kuraigahara Hut giving people access to one of the best spring backcountry areas in Japan and a chance to walk along a deep snow wall. Bus service will open to Tatamidaira by the beginning of June. You can find more info about the Alpico bus schedule here and also check out Kuraigahara’s homepage here (sorry it’s only in Japanese).
If you have any questions about Norikura Kogen please leave a comment and I will do my best to answer your questions.