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. A nuruyu (ぬる湯) is a bath close to body temperature rather than the usual scalding heat. Some springs simply rise from the ground that warm and are served exactly as they come; other facilities deliberately cool their baths to below 40°C (104°F) for this event. Either way, it is the slow food of Japanese bathing: you stay in for an hour instead of three minutes, the minerals work quietly, and 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 are collected in TIPS, Shizuoka's official tourism app, one stamp per facility after your soak.

• 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 member facilities, plus a prize lottery.
• 6 stamps: a guaranteed bath-discount coupon, plus a lottery for facility towels and other goods.
• Prize applications go through the app until October 9, 2026.

The twelve baths

The roster spans the whole prefecture, and the variety is the point:

• 畑毛温泉 富士見館 (Hatake Onsen Fujimikan), a 1910 therapeutic-stay ryokan whose three-tier Choju-no-yu (長寿の湯) baths step from lukewarm to hot.
• The 梅ヶ島 (Umegashima) mountain cluster north of Shizuoka City: Baikunro (梅薫楼), Yu no Yado Ichikawa (いちかわ), and Yunoshimakan (湯の島館).
• City-run mountain baths like 口坂本温泉浴場 (Kuchisakamoto) and やませみの湯 (Yamasemi no Yu), and the seaside hall さがら子生れ温泉会館 (Sagara Koumare Onsen Kaikan) with its child-birth-stone legend.
• Izu-side soaks from 源泉 駒の湯荘 (Koma no Yuso) to the 七滝温泉ホテル (Nanadaru Onsen Hotel) in Kawazu, plus 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, which is also the most energy-honest way to run a bath. Shizuoka has one of Japan's richest concentrations of these springs, from Hatake Onsen's designated recuperation area to the 30-degree pools of the Shizuoka City mountains.

Editions

The rally is seasonal and evolves year to year. The 2025 edition was paper-based, with stamps inked onto a flyer; 2026 moved everything into the TIPS app. 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. The rally returns in new seasons, and so does the badge: it is repeatable per edition.