A New Summer Norm in Hiroshima!? Enjoy 'Cold Hot Springs' This Summer – #HiroshimaSummerOnsen Campaign Launch

While Hiroshima Prefecture may not be widely recognized for hot springs, it actually leads Japan in the number of cold mineral springs—defined as sources below 25°C*. Often mistaken for groundwater due to the name, cold mineral springs are officially recognized as legitimate hot springs under Japan's Hot Springs Act. To combat the anticipated summer heat, Hiroshima's prefectural SNS platform 'Nichinichi Washira' is introducing the concept of 'bathing in cold hot springs during summer' as a new norm. The collaborative campaign '#HiroshimaSummerOnsen' partners with local bathhouses offering natural, flowing cold springs. Now in its third year, the campaign has already recognized 32 'Hiroshima Summer Onsen Ambassadors' and continues to gain popularity. We welcome media coverage and introductions to participating facilities and experts.

*Source: Ministry of the Environment, 2024 Survey on Hot Spring Utilization

Past Success: 32 'Hiroshima Summer Onsen Ambassadors' Certified by Visiting 7 Local Springs

Participants simply visit seven designated facilities in Hiroshima Prefecture that offer natural-flow low-temperature or cold mineral springs, photograph a designated marker near the reception, and post it on 'Nichinichi Washira'. Titles are awarded based on the number of facilities visited, with full completion earning the title of 'Hiroshima Summer Onsen Ambassador' and an official certificate.

※ Participants who received certificates in the previous or two years prior will receive new certificates marked with '★★' or '★'.

※ The first 30 completers will receive a limited-edition 'Hiroshima Summer Onsen' tenugui (hand towel).

※ In August, visiting six facilities (excluding Hiroshima Kita Hotel) qualifies participants for the Ambassador title.

Don't miss the video by campaign ambassador Nakano Kazuyuki, a温泉 sommelier and photographer, sharing the wonders of summer onsen.

YouTube Video: 【New Fact】Hiroshima is a Summer Onsen Paradise (https://youtu.be/t7vkrVBxMnU?si=NzWKWs43Uf7XG2r0)

【Participating Facilities】

❶ Genyu Kosegawa Onsen (Hatsukaichi City) – One of the highest radon-content springs in the Chugoku region

Water is pumped directly from underground, maintaining a temperature of 15–16°C even in summer, and as low as 10°C in winter. Guests can bathe in the source water as-is in the indoor cold bath. A free take-home station for spring water is also available near the parking lot.

❷ Yuki Lodge (Higashi-ku, Hiroshima City) – Ideal for beginners to cold onsen

The bath next to the sauna is unheated and fed by natural flowing spring water. At 28.3°C, this low-temperature spring is warmer than typical cold baths (below 25°C), reducing physical strain. The outdoor bath overlooks the Mizunai River, enhancing the refreshing experience.

❸ Yunoyama Onsenkan (Higashi-ku, Hiroshima City) – A cool shower-style bath with historical roots

Perfect for summer, this facility offers a continuous flow shower using 23.5°C cold mineral spring water, cascading from 4 meters above. The source spring above is part of the nationally designated Important Tangible Folk Cultural Property, 'Yunoyama Myojin Old Spa Town', where feudal lords of the Asano clan once bathed during the Edo period.

❹ Tsurunoyu (Kure City) – A traditional public bath where even the sauna uses spring water

A classic sento (public bathhouse) with a 18°C spring source, nearly as cool as tap water. The cold bath at the back uses this spring in a free-flow system. All bathwater and heated water are sourced directly from the spring—a rarity nationwide. Even the mist in the wet sauna uses the spring water.

❺ Kagura Monzen Tojimura (Akitakata City) – Cloudy spring water that elevates the onsen experience

The second-floor cold bath uses unheated spring water, allowing direct immersion in cold mineral springs. Slight cloudiness on certain days enhances the authentic onsen feel. Adjacent to a sauna, it allows users to cool down in the cold spring after heating up.

❻ Kobi Natural Hot Spring Gran-no-Yu (Fukuyama City) – A smooth, skin-beautifying summer onsen

Conveniently located next to a large commercial complex's parking lot, this facility houses a rare cold spring in the Bingo region. Inside the spacious bathhouse, the central indoor bath is labeled 'Fresh Spring Flow'. With a source temperature of around 26°C, it's warmer than typical cold baths and easier to enter.

❼ Hiroshima Kita Hotel (Kitahiroshima Town) – Spring water from every tap in the building

With the lowest source temperature among participating facilities at 15.7°C, it contains 27mg of free carbon dioxide. Day-trip bathing is available: men's bath on the 2nd floor, women's on the 1st. Cold mineral spring flows from every tap, allowing guests to enjoy the source water directly in the large cold bath. All guest room bathtubs are also filled with spring water.

Note: Day-trip bathing is unavailable from early to late August due to private bookings. Please inquire before visiting.

【Campaign Overview】

Period: July 1, 2026 (Wed) – September 30, 2026 (Wed)

Eligible Facilities: 7 facilities in Hiroshima offering natural-flow cold hot springs

Participation Methods:

【Complete Prize】Only for those who visit all 7 facilities – 'Hiroshima Summer Onsen Ambassador' Certificate

① Pre-register on 'Nichinichi Washira', Hiroshima's official SNS

② Visit each facility and photograph the designated marker near reception

③ Post the photo on 'Nichinichi Washira' with the hashtag #HiroshimaSummerOnsen

④ Once all 7 posts are complete, submit required details via Google Form

⑤ The editorial team verifies completion and sends the certificate

【Double Chance Prize】Limited tenugui for first 30 completers

The first 30 participants to complete all 7 facilities receive a special 'Hiroshima Summer Onsen' tenugui

【Lucky Prize】Win even with one visit – Original T-shirt Course

① Pre-register on 'Nichinichi Washira'

② Visit any facility and photograph the marker

③ Post with #HiroshimaSummerOnsen on 'Nichinichi Washira'

④ Attach the entry coupon from the July issue of 'TJ Hiroshima' (on sale June 25) to a postcard and mail it

⑤ 10 winners selected by lottery receive an original 'Hiroshima Summer Onsen' T-shirt

Summer Onsen Ambassador: Kazuyuki Nakano,温泉 Sommelier & Photographer

【Facility Selection & Production】

A freelance photographer based in Hiroshima, originally from Miyagi Prefecture, specializing in onsen photography. Has visited over 500 hot springs across the Chugoku and Shikoku regions. One of only a few in Japan to hold the 'Two-Star温泉 Sommelier' certification. Published works include '温泉 Sommelier Kazuyuki Nakano's精选 Guide to Flowing Springs in Chugoku & Shikoku' and 'OnTetsu: Riding Local Trains to Hot Springs' (Za Mediajon)

https://onsen-photographer.amebaownd.com

Nichinichi Washira

Tagline: 'Only Hiroshima topics. The world's first prefectural SNS?' Launched in 2017 as a dedicated social platform for all who love Hiroshima.

User base: Approximately 16,000 (as of June 2026)

https://washira.jp/