The only sponsored event in Japan that I know of. The site is in Japanese and some details for any hangers living in Tokyo:
https://thetrailsmag.com/archives/10152
Two day event l starting on May 13 with an optional overnight hang at the campsite.
Registration begins April 7th.
Location is in Otsuki, about 80 minutes from Shinjuku station via JR Chuo lines.
I registered for the event last year but had to cancel because my kid had her undokai :/
Hoping things work out this year...
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