Hot springs are undoubtedly one of Japan’s most cherished treasures, both at home and abroad. Whether nestled within luxurious resorts or emerging from serene, secluded settings, onsen are a true symbol of Japanese culture. But their significance goes beyond mere relaxation; they also hold a rich historical legacy. Here’s a look at the world’s oldest onsen inn.
A 1300-year history
Japan boasts a wealth of natural treasures, and onsen are definitely a highlight. Some of these hot springs have maintained their charm for centuries. Among them, the oldest is Keiunkan, nestled in the quaint Nishiyama Onsen area, where history and beauty come together seamlessly.
Located in Hayakawa Town in southwestern Yamanashi Prefecture, this onsen is set in a fairy-tale landscape. With 96% of the area covered in lush forests and the clear waters of the Hayakawa River nearby, it’s a nature lover’s dream, complete with beautiful waterfalls and gorges. This region also holds historical significance as an ancient spiritual site, thanks to its close ties to Minobu Mountain, a gold mining hub during the Sengoku period.
This ryokan has roots that stretch back to 705 AD during the Asuka period, giving it an incredible history of over 1,300 years. It earned the title of “world’s oldest hot spring inn” from Guinness World Records in 2011.
Keikunkan is one of three inns in Nishiyama Onsen and has never run dry throughout its long existence. Its lasting charm has attracted numerous historical figures who have come to enjoy and fall in love with this onsen.
At Keikunkan, visitors can enjoy six unique types of baths, each offering something special. Two outdoor baths immerse guests in nature, creating a dreamy experience with soothing sounds all around. There are also two observation baths on the top floor, offering breathtaking views of the untouched landscape. And for a more intimate experience, there are two exclusive private outdoor baths crafted from beautiful stone.
Nature’s timeless healing
Hot springs have been a cherished part of Japanese culture for centuries, with evidence of their enjoyment dating back just as long. Ancient texts often highlight the significance of onsen. The earliest mention comes from the Fudoki, which notes Prince Shōtoku’s visit to Dogo Onsen in Matsuyama, Ehime, in 596 AD.
Later, the Engishiki (905–927 AD) also emphasizes onsen as key pilgrimage stops. These texts paint hot springs as perfect places for travelers to refresh their bodies and souls before embarking on their spiritual journeys.
Back then, hot springs were deeply spiritual, celebrated as divine sources with healing and purifying powers. For ancient people, the naturally flowing hot springs were invaluable, especially since manually heating water was a labor-intensive task. This practicality, along with the beneficial minerals in the water, made hot springs a revered symbol of ancient Japan. Interestingly, this echoes the role of hot springs in ancient Rome, where “Roman baths” held similar significance in society.
Japanese onsen have thrived ever since, thanks to the country’s unique geography. Volcanic regions provide the perfect backdrop for hot springs, where magma erupts and turns into lava. This intense heat, combined with rain, snow, and seawater, fuels many of Japan’s iconic hot springs. Interestingly, non-volcanic hot springs now outnumber volcanic ones, typically formed by drilling underground, where temperatures soar the deeper you go. The deepest hot spring well in Japan, in Rokkasyo village, Aomori, reaches an impressive 2,714 meters and boasts a steamy 92-degree temperature.
As of March 2018, the Ministry of the Environment reported 2,983 hot springs across Japan. While the count exceeded 3,000 in 2010, it has since seen a decline. Hokkaido tops the list with the most onsen, boasting 244, followed closely by Nagano with 215, Niigata with 145, and Fukushima with 136.
A journey through time
Given the special place onsen hold in Japanese culture, it’s no wonder that Keikunkan, with its rich history, occupies an even more cherished spot. Its story dates back to 705 AD when Fujiwara no Kamatari’s eldest son, Fujiwara no Makoto, stumbled upon the hot spring while hunting. Since then, the Fukuzawa family has taken the helm, elevating its reputation as a premier ryokan.
Famed for its healing properties, Keikunkan attracted shoguns and vassals alike. However, it was also a beloved retreat for locals. Many farmers from Yamanashi Prefecture would bring food and linger for long stays during the off-seasons—a practice fondly known as “self-catering healing.”
These habits brought in a nice revenue boost for the onsen by cutting out the costs of providing food. Plus, its secluded location in the mountains made it a sought-after getaway, free from competition. Under the leadership of its 52nd head, Yuji Fukuzawa, Keikunkan began a new chapter. Starting in the 1970s, the ryokan underwent renovations that shifted its focus toward tourism, gradually moving away from the healing traditions it was once known for.
With significant renovations, the new head brought in 60,000 visitors annually by 1975, transforming Keikunkan from a humble healing spot into an exclusive ryokan. A pivotal moment came in 2005, during the ryokan’s 1,300th anniversary, when management drilled for a new hot spring source. They hit a well that produced an impressive 1,630 liters per minute at 53 degrees, adding to the onsen’s appeal. This led to unfiltered hot springs in every room, which has truly won over travelers from near and far.
The downside of longevity
Keiunkan’s 1,300-year history hasn’t been without its challenges. The stunning natural landscape that surrounds the ryokan has also brought its fair share of trouble.
The usually peaceful Hayakawa River can turn turbulent during heavy rains, causing floods that have wiped out entire buildings over the centuries. Other natural disasters struck too—two forest fires in the Meiji era, a rockfall that destroyed a building in the Taisho era, and another rockslide in 2010 that blocked the main road.
One of the toughest moments came in 1982 when a typhoon swept away part of the building. Many believed that this marked the end of Keiunkan’s millennium-long history. However, its head, Yuji Fukuzawa, saw this tragedy as the perfect opportunity to begin renovations and turn his vision of an exclusive, high-end ryokan into a reality.
Of course, the challenges didn’t end there. The 2011 Great East Japan Earthquake and the drop in tourism brought fresh financial pressures, leading to joining the larger, more secure Nishiyama Onsen group. Then came the extended closure due to the global health crisis, which prompted a reduction in rooms to ensure guest safety.
But beyond its timeless charm, it’s Keiunkan’s ability to evolve and adapt that has kept it standing through centuries. As Professor Toshio Goto from the Japan University of Economics, an expert in long-lived businesses, puts it:
“Long-established hot spring ryokan benefit from having their own water sources. Historically, hot springs were vital for healing, and how they were managed—either as private resources or shared with the community—played a big role in shaping local economies. Focusing on long-term goals rather than short-term gains is key to the longevity of these businesses.”
Embracing the future
Despite more than 1,300 years of challenges, Keikunkan ryokan continues to thrive under the leadership of Kenjiro Kawano. Reflecting on the obstacles he faced as the new general manager, Kawano said:
“They warned me it wouldn’t be easy, but after working here for so long, I couldn’t let Keiunkan fade away. I knew I was the one who could help secure its future, so I took on the responsibility.”
Today, about two-thirds of Keikunkan’s guests come from the Kanto region, with just 5% from Yamanashi, where the ryokan first thrived. Although it remains rooted in the millennia-old traditions that built its reputation, Keikunkan is on the brink of a new chapter filled with changes and forward steps.
While its secluded mountain location adds to Keikunkan’s charm, it has also posed challenges for its evolution. That’s why the management welcomes the nearby construction of the Linear Chuo Shinkansen tunnel, which will enhance accessibility. Soon, the journey to Kofu will take just one hour from Tokyo, with the existing road to Keiunkan linking to additional routes.
Overall, while valuing its unique natural setting, the inn and its management are eager to embrace future opportunities. Though some elements of its ancient character may get lost along the way, these changes will ensure that this historic heritage doesn’t vanish under the hustle and bustle of modern tourism.
Visiting Keiunkan
While most of Keiunkan’s visitors come from Yamanashi, the location welcomes inbound travelers. Consider Keiunkan while seeing other sites around Yamanashi Prefecture, such as Mt. Fuji. You can make reservations from Keiunkan’s English language Website.
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Sources
【こだわりの宿特集】慶雲館（山梨県・西山温泉） 関東経済新聞
世界最古「甲斐の秘湯」はなぜ1300年続いたのか 日経ビジネス
第1章 湯治場としての温泉 本から広がる温泉の世界
温泉の歴史（古代）※奈良時代～平安時代 日本温泉協会
日本の温泉データ 日本温泉総合研究所
温泉豆知識 日本に温泉が多い理由とは ハルメク
