Shizuoka Nuruyu Stamp Rally

ぬる湯スタンプラリー (Nuruyu Stamp Rally) is a seasonal rally across the lukewarm springs of Shizuoka, run by the prefecture's onsen association. Nuruyu (ぬる湯) is their word for a bath close to body temperature, which the association pins at roughly 36 to 39°C, instead of the usual scalding heat. It is the slow food of Japanese bathing: you stay in for an hour rather than three minutes, the minerals work quietly, and where the spring already rises that warm, nothing has to be heated at all. On a hot day it is the most refreshing bath there is.

The summer 2026 edition

The 2026 rally, subtitled 夏の陣 (Natsu no Jin, "the summer campaign"), runs from July 7 to September 30, 2026, and is the association's first fully digital edition. Stamps live in TIPS (Tourism Information Platform of Shizuoka), the prefecture's official tourism app, so there is no paper card to lose.

1. Install TIPS.
2. Open the stamp rally section and register for ぬる湯スタンプラリー.
3. Visit a member bath, soak, and collect the digital stamp there. One stamp per facility.
4. Reach six or twelve, then send the prize form from inside the app.

No entry or certification fee is listed for 2026, so beyond the usual bathing charges the rally costs nothing. There are two finish lines.

Six stamps: the Nuruyu Thanks Coupon

Everyone who reaches six baths gets ぬる湯サンクスクーポン2026 (Nuruyu Thanks Coupon), a sheet of discounts donated by member facilities:

• Sagara Koumare Onsen Kaikan (さがら子生れ温泉会館): a four-hour adult bath at ¥500, honoured at that price even after the hall revises its rates
• Hatake Onsen Fujimikan (畑毛温泉 富士見館): ¥100 off the bath
• Nanadaru Onsen Hotel (七滝温泉ホテル): ¥100 off
• Yu-gokoro no Yado Ichikawa (湯心の宿 いちかわ): ¥100 off
• Gensen Koma no Yuso (源泉 駒の湯荘): ¥100 off

Six stamps also enter you in a draw, five winners for each prize:

• Mine Onsen Daifunto Park (峰温泉大噴湯公園): a voucher for an onsen egg boiled in the geyser, one per person
• Kuchisakamoto Onsen Yokujo (口坂本温泉浴場): an original onsen towel
• Yamasemi no Yu (やませみの湯): an original onsen towel
• Shizuoka Prefecture Tourism Association: lava-roasted Mt. Fuji coffee bags, 8 g × 3

Twelve stamps: the Nuruyu Passport

Finish all twelve and you get ぬる湯パスポート2026 (the Nuruyu Passport) plus an original certificate of completion. The passport is a booklet of free-bath perks put up by the members:

• Hotel Baikunro (梅ヶ島温泉ホテル梅薫楼): a free bath, book ahead
• Omoide no Yado Yunoshimakan (おもいでの宿 湯の島館): a free bath, book ahead
• Sagara Koumare Onsen Kaikan (さがら子生れ温泉会館): four hours free for one adult, children welcome too

And a second draw:

• Yudai Onsen (ゆうだい温泉): a free bath, 10 winners
• Suruga no Yu (沼津温泉 駿河の湯): a one-day pass, 10 winners
• Gensen Koma no Yuso (源泉 駒の湯荘): a one-day pass with a towel, 5 winners

Claiming a prize

The prize form sits inside the app and closes on Friday, October 9, 2026. Everything happens after that date: the draws are made once applications close, and winners are announced only by the parcel turning up. The organisers add a practical warning, which is easy to trip over with a digital rally: your completed stamp screen disappears once the deadline passes, so screenshot it first if you want to keep it.

If a member is shut for the day or has a bath down for maintenance and you cannot get its stamp, the office can arrange a substitute or relax the completion requirement at their discretion. Worth asking rather than writing off the set.

The association also posts a printable 12湯チェックシート (12-bath check sheet, PDF) on the rally page: one line per bath for the date you soaked and what you made of the water, for anyone who likes a record outside the app.

Rally office (ぬる湯スタンプラリー事務局), inside the Shizuoka Prefecture Onsen Association: 054-221-3281, weekdays 10:00 to 16:00, [email protected].

The twelve baths

The roster spans the whole prefecture, and the variety is the point. The temperatures below are the association's own figures.

• 畑毛温泉 富士見館 (Hatake Onsen Fujimikan) in Kannami, a therapeutic-stay ryokan founded in 1910. Its Choju no Yu (長寿の湯) steps through three tubs at about 33, 38 and 41°C off a 33°C spring, so you can work up and back down.
• The 梅ヶ島 (Umegashima) mountain cluster north of Shizuoka City: Baikunro (梅薫楼), pouring its 39°C source straight into the tub, Ichikawa (いちかわ), where every bath inside and out runs kakenagashi at around 38°C, and Yunoshimakan (湯の島館).
• City-run mountain baths: 口坂本温泉浴場 (Kuchisakamoto), a silky 37.5°C spring held at 37 to 39°C, and やませみの湯 (Yamasemi no Yu) up the Nishizato valley in Shimizu.
• さがら子生れ温泉会館 (Sagara Koumare Onsen Kaikan), a hall in the hills of Makinohara named for the local child-birth-stone (koumare-ishi, 子生れ石) legend.
• Izu-side soaks: 源泉 駒の湯荘 (Koma no Yuso) in Izunokuni, all kakenagashi with tubs from 36 to 41.5°C, the 七滝温泉ホテル (Nanadaru Onsen Hotel) in Kawazu, and the free foot bath at 峰温泉大噴湯公園 (Mine Onsen Daifunto Park), where a geyser has been erupting on schedule since 1926.
• Bigger day-use spots too: ゆうだい温泉 (Yudai Onsen) in Mishima and the 駿河の湯 (Suruga no Yu) complex in Numazu.

Why nuruyu in summer

The association's pitch is simple: lukewarm bathing is what onsen culture looks like in the heat. Where the spring itself rises lukewarm, you soak in the source exactly as it comes, with no heating and no boiler, which is also the most energy-honest way to run a bath. Long soaking is where the rest of it comes from as well: the association talks about relaxation, warmth that stays with you afterwards, and a bath you can take season after season without fighting the temperature. Shizuoka has one of Japan's richest concentrations of these springs, from the Hatake Onsen recuperation area to the 30-degree pools of the Shizuoka City mountains.

Editions

The rally is seasonal and changes shape year to year. The 2025 edition, しぞ〜かぬる湯温泉スタンプラリー, ran from August 29 to October 31 with eleven baths and a paper flyer that facility staff stamped by hand. Certification cost ¥500, and finishers ordered a keepsake carrying the rally's Nuruyu Neko (ぬる湯ネコ) cat mascot: a 56 mm can badge for ¥300, a 53 mm acrylic keyring for ¥500, or a 20 cm microfiber handkerchief for ¥1,000, each in a choice of three illustrations, plus a certificate with their name on it. Fourteen people finished all eleven.

For 2026 everything moved into TIPS, and the roster was reshuffled: five baths carried over, six sat out, and seven joined, including the first foot bath in the set. Onsen Oni tracks the current roster on this page.

Earning the Onsen Oni badge

The Nuruyu Lover (Shizuoka) badge is awarded by Onsen Oni moderators once you've collected all twelve stamps of an edition. A screenshot of your completed stamp screen in the TIPS app, sent through the feedback channel, is enough (and you need that screenshot for yourself anyway). The rally returns in new seasons, and so does the badge: it is repeatable per edition.