# The Sonomama Festival 2026
_そのまままつり2026_

- **When:** Wed, Nov 11, 2026 (JST)
- **Where:** Shima Onsen Kusushiki — Shima 3826-1, Nakanojo, Agatsuma
- **Price:** price on the official site
- **Category:** Cultural & Ethnic Festivals
- **Official site:** https://mamama2026.peatix.com/
- **On Tokyo Events:** https://eventstokyo.com/en/events/the-sonomama-festival-2026

![](https://cdn.peatix.com/event/4807430/cover-o4bjvxDZr5QNxcvquRmITyhN1vrB73oe.png)

Held in the Shima hot spring area of Gunma Prefecture, the unique Sonomama Festival invites participants to write their usual titles on paper and float them down the river. People freely play on a large sheet of Japanese paper while smearing mud on each other. The event encourages letting go of daily roles and societal expectations to simply be human for a day. Starting in 2025, this will be its second year. Visitors can join the mud play or observe only. Afterward, participants can enjoy bathing in the Shima hot springs.

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Source: Tokyo Events — https://eventstokyo.com/en/events/the-sonomama-festival-2026