The Shizuoka Nuruyu Stamp Rally is live, and every bath is on Onsen Oni

Back in May we wrote about a summer stamp rally the Shizuoka Prefecture Onsen Association was planning around the prefecture's nuru-yu, its gentle, lukewarm springs. Today it's official: the ぬる湯スタンプラリー2026 夏の陣 (Nuruyu Stamp Rally 2026, "the summer campaign") launched, and it runs from July 7 to September 30, 2026.

We didn't just report on it this time. All twelve participating baths are now in the Onsen Oni catalog, gathered on our new program page:

The confirmed rules

The biggest change from the early plans: this is the association's first fully digital rally. Stamps are collected in TIPS, Shizuoka's official tourism app. Visit a participating bath, soak, get your in-app stamp.

• All 12 stamps: the Nuruyu Passport (ぬる湯パスポート), a booklet of free-bath coupons and perks donated by the facilities, plus a prize lottery.
• 6 stamps: a guaranteed bath-discount coupon, plus a lottery for facility towels and other goods.
• Prize applications run in the app until October 9, 2026.

Twelve very different baths

The roster spans the whole prefecture, and that's the fun of it. A few highlights:

• Hatake Onsen Fujimikan (畑毛温泉 富士見館), a therapeutic-stay ryokan from 1910 whose three-tier Choju-no-yu (長寿の湯) lets you ladder from a 32-degree lukewarm pool to a properly hot one.
• Mine Onsen Daifunto Park (峰温泉大噴湯公園) in Kawazu, where a geyser has erupted on schedule since 1926 and the stamp comes with a free foot bath.
• Yamasemi no Yu (やませみの湯), a city-run bath in a forest park with a source-fed lukewarm tub, named after the kingfisher on the river beside it.
• The Umegashima (梅ヶ島) mountain cluster north of Shizuoka City, plus city halls, a Numazu super-sento, and Izu inns. The full list is on the program page.

Why lukewarm, again?

Because the water goes unheated, you're soaking in the source exactly as it rises, and in summer that's the whole appeal: settle in for an hour, let the minerals work, come out refreshed instead of boiled. If you're in Shizuoka before the end of September, this is about the most pleasant homework an onsen lover can get.

For the authoritative rules, see the official rally page from the association.