Beyond providing a sense of purification and relaxation, Japanese onsen (hot springs) offer a unique opportunity to reconnect with nature. However, some “hidden onsen” excel in this regard more profoundly than others.
Some of these thermal havens are hidden off the common path, nestled in secluded natural corners that often escape the notice of the unprepared traveler. Yet their pristine beauty is a must-experience at least once in a lifetime.
Hidden onsen: Just out there, off the beaten track
Hidden within the intricate embrace of nature, secret hot springs bear the name “hitou” (秘湯), a term first coined in 1975 by Ichizo Iwaki, the founder of the Asahi Travel Club. Initially numbering around 33, they earned the “hidden” label due to their secluded locations deep in the mountains or at the tip of a cape.
Later organized under the Japan Association for the Preservation of Hidden Hot Springs, these springs proved challenging for travelers to reach or even notice. Essentially, they were remote, far from the hustle and bustle of human activities, ensuring their pristine beauty remained undisturbed and untouched.
Hidden onsen were once a well-kept secret. Until they weren’t anymore. The term “hitou” gained traction among those seeking genuine nature experiences.
In these concealed spots, the hot spring encounter became more authentic. While popular hot spring towns bustled with tourists and commercial activities, secret onsen held their ground, shielded from over-spoiling. Dr. Tadanori Matsuda, also known as Professor Onsen, wrote a book on this enchanting natural phenomenon titled “Hidden Hot Springs,” adding to their growing popularity.
A medicine for body and soul
Curious about the onsen backstory? Think of it as nature’s gift to Japan. Nestled in a volcanic belt, Japan is home to about 7% of the world’s active volcanoes.
It might not sound very tempting, right? Yet it’s this very volcanic presence that birthed the beloved hot springs. When rain and snow met underground magma, it became a special heated water that bubbles into the onsen we all cherish today. (It also helped create some places that are, literally, hell on earth.) With these unique natural features, Japan boasts approximately 27,000 hot spring sources and 3,000 onsen resorts.
Onsen are ingrained in Japanese culture, with a history of 1,300 years. The earliest references to onsen can be found in historical documents like Kojiki and Nihon Shoki, the oldest records of Japan, dating back to the Nara period. In those times, onsen held a sacred status, affectionately dubbed “shinyu” (神湯) or divine hot springs.
Ancient annals point to “Iyo no Yu” in Ehime Prefecture, “Muro no Yu” in Wakayama, and “Arima no Yu” in Hyogo as the “Three Ancient Hot Springs of Japan,” favored retreats among emperors. Initially exclusive to high-ranking individuals, onsen later opened their doors to all, thanks to the influence of Buddhist Zen monks. The tradition of immersing oneself in hot waters gained momentum alongside the belief in their therapeutic properties.
Today, we may not necessarily swear by the mystical healing powers of spring waters. Yet, there’s no doubt that the volcanic minerals within offer a host of benefits for both body and spirit.
All the way to modern tourist hubs
In Japan, hot springs were more than just a place to relax — they were deeply intertwined with therapeutic medicine. People journeyed from every corner to soak in these rejuvenating waters and ease their pains. During the Edo period, improved highways and infrastructure made the journey to onsen more accessible. This sparked the rise of inn-based hot springs and resorts featuring multiple thermal water springs.
What started as a healing ritual gradually evolved into a blend of leisure and amusement, infusing a fresh social dimension into the onsen experience
The 1970 Osaka World Exposition sparked a notable shift in Japan’s travel scene, fueling a surge in both domestic and international tourism. Onsen, having evolved and modernized, became integral to this period. The so-called Onsen Boom ushered in a new chapter in the history of hot springs in Japan. Riding the wave of growing travel industries and economic prosperity, hot springs evolved into hotels and sought-after tourist spots.
It evolved into a whole new business, with inns seizing the prime advantages. Mainly situated in mountainous and coastal areas easily connected to the rest, these establishments flourished during the boom years.
“The true essence of travel”
In the midst of it all, small hot spring inns with limited capacity and remote locations were somewhat overlooked. Some struggled to keep up with modernization, while others were simply too far off the usual route to garner attention. Yet, as Ichizo Iwaki pointed out, these places encapsulated the real essence of travel — a spirit that pays no mind to inconvenience or inefficiency but instead craves the exploration of the new.
Ichizo Iwaki envisioned a revived future for these hidden treasures. He yearned for the day when people would return to the nostalgic nature of travel and rediscover them. He didn’t have to wait long for that moment. In 1982, Asahi brought the third edition of his “Secret Hot Springs of Japan” to life as a TV program. Soon after, the “hitou boom” emerged, creating a newfound fascination with secret springs and the simplicity of connecting with nature.
Hidden onsen you can’t miss
Thinking about your first hidden onsen getaway? Here are three recommendations. While some may pose a challenge to reach, the experience is worth it.
At the top of our list is the original secret gem of hot springs – Tsurunoyu Onsen in Senboku, Akita Prefecture, known as the birthplace of the hidden onsen boom. Dating back to the Edo period, it was a favorite among samurai. The journey isn’t a walk in the park, navigating through pitch-dark mountain roads and unpaved streets. However, the reward is immediate – a pristine view devoid of streetlights and traffic noise. It’s just you and nature. The milky white outdoor bath (known as “白湯” or “white hot water”) is the highlight, bubbling up with high sulfur content, perfect for the skin.
Known as Japan’s toughest reservation, Sennin Onsen rests in Suzaka, Nagano Prefecture. Its air of mystery starts with a reservation system open by phone only on the first day of each month, a whopping 11 months ahead. The secrecy doesn’t stop there; the inn is nestled away from the bustle of daily life, surrounded by refreshing natural scenes. A standout feature is the cave bath (岩の湯), where rock gates create an entrance to another world.
Last but not least, Furou Fushi Onsen in Fukaura, Aomori Prefecture. This onsen is immersed in nature, at the base of the UNESCO-listed Shirakami mountains and boasting a coastal view of the Sea of Japan. Legend has it that its name – it literally means “immortality” – stems from the old saying, “If you take care of yourself here, you will never grow old or weak.” The stunning open-air tub is just about a meter from the shore, providing a distinctive onsen experience with the sea breeze.
Preserving the beauty of hidden onsen
Today, the world is well aware of hidden onsens. That’s why the Japan Association for the Preservation of Hidden Hot Springs strives to preserve their authenticity amidst the challenges of modern tourism. As their popularity soars, it’s vital to protect these spots and avoid overexploitation. After all, these hidden gems are a special gift from the Earth to Japan.
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日本秘湯を守る会について 日本秘湯を守る会
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