The Oldest Known Hot Spring in Shiga Kogen
Happo Onsen is regarded as the oldest known hot spring in Shiga Kogen. At one point in its history, it was also considered part of Heion Onsen, an older name associated with what is now the Yudanaka-Shibu Onsen area.
The surrounding highlands have since developed into a major ski and mountain resort, but Happo Onsen retains a strong connection with the history of hot spring culture in the region.
The Unique Hot Spring Water of Happo Onsen
Several Types of Hot Spring Water
Happo Onsen is known for several types of mineral spring water, including simple hot spring water, simple sulfur hot spring water of the hydrogen sulfide type, and hydrogen sulfide spring water.
The water has a pH of approximately 5.4. Although it is clear and colorless, it carries a distinctive sulfur character and the characteristic aroma of hydrogen sulfide.
A Rare “Steam Hot Spring” System
One of the most unusual features of Happo Onsen is the way its hot spring water is prepared. The source temperature is approximately 50°C, while high-temperature steam emerges directly from the surrounding rock.
This natural steam is captured and converted into hot water using a dedicated kettle-like system. The heated water is then mixed with water flowing from a mountain stream before being used for bathing. This unusual method is known as a “steam hot spring” system and is a distinctive feature of Happo Onsen.
A Mountain Resort Shaped by Ski Tourism
Today, Happo Onsen does not resemble a traditional Japanese hot spring town lined with old wooden inns. Instead, the area has developed mainly as a collection of ski hotels on the mountainside.
Although much of the atmosphere of the former hot spring retreat has disappeared, its location provides a unique combination of highland scenery, winter sports, and hot spring bathing.
A Connection with the 1998 Nagano Winter Olympics
During the 1998 Nagano Winter Olympics, Mount Higashidate in Shiga Kogen was used as the venue for the alpine skiing giant slalom events. Happo Onsen is located on the mountainside below the ski area.
As a result, the area becomes particularly lively during the winter season, when visitors can enjoy skiing and other snow activities before returning to the warmth of a hot spring bath.
The History and Name of Happo Onsen
The Discovery of Tengu-no-yu
The recorded history of Happo Onsen dates back to 1841, during the Tenpo era of the Edo period. According to local tradition, a man named Shinsaku Seki discovered a hot spring known as Tengu-no-yu, which is regarded as the origin of the present-day hot spring.
The hot spring was also mentioned in the diary of Sakuma Shozan, a prominent thinker of the late Edo period. This historical record provides another connection between Happo Onsen and the intellectual and cultural history of nineteenth-century Japan.
Why Is It Called “Happo”?
There are several theories about the origin of the name “Happo.” One explanation refers to the sound of hot steam bursting from the ground, described as making a rhythmic “poppo, poppo” sound.
Another theory suggests that travelers became increasingly warm and flushed as they climbed the steep mountain route toward the hot spring, leading to the expression “hoppo, hoppo” to describe their heated bodies.
Although the exact origin remains uncertain, both stories reflect the close relationship between the name of the hot spring and its distinctive mountain environment.
A Hot Spring Loved by Writers and Artists
The magnificent views and peaceful mountain setting of Happo Onsen attracted numerous writers and cultural figures in the past. Among them was the poet and writer Tatsuji Miyoshi, who stayed in the area for extended periods.
Miyoshi praised Happo Onsen for its extraordinary scenery, describing its magnificent views as a kind of secluded delight beyond the ordinary world.
Several historic hot spring facilities, including Tengu-no-yu and Yakushi-no-yu, once operated in the area. Unfortunately, these establishments are no longer open, but their names remain part of the history of Happo Onsen.
Hot Spring Facilities Available Today
Visitors can still enjoy day-use bathing at several accommodation facilities in the Happo Onsen area, including:
Nishi Happo Onsen Hotel
Liberty Shiga
Hotel Higashidate
These accommodations are known for their abundant hot spring water and offer baths supplied by natural hot spring water flowing directly from the source. After a day of skiing or hiking in the mountains, soaking in the warm mineral water provides a relaxing way to recover while enjoying the atmosphere of the highlands.
Getting to Happo Onsen
By Train and Bus
From JR Nagano Station, take a Nagano Dentetsu bus on the Express Shiga Kogen Line. The journey takes approximately 1 hour 40 minutes, followed by a stop at Happo Onsen.
From Nagano Dentetsu Yudanaka Station, buses bound for Shiga Kogen take approximately 60 minutes to reach Happo Onsen.
By Car
From the Shinshu-Nakano Interchange on the Joshin-etsu Expressway, Happo Onsen is approximately 30 kilometers via National Route 292.
The Former Shiga Kogen Ropeway
In the past, visitors could also reach the area using the Shiga Kogen Ropeway from Happo Onsen Station. However, operations were suspended on May 25, 2011, and the ropeway was subsequently discontinued.
A Historic Mountain Hot Spring in Shiga Kogen
Happo Onsen combines highland scenery, a long history, and unusual natural hot spring resources. Its elevation of 1,600 meters provides expansive mountain views, while its distinctive steam-based hot spring system makes it particularly interesting for travelers curious about Japan’s diverse bathing traditions.
The experience is especially rewarding when combined with the outdoor attractions of Shiga Kogen. In winter, visitors can spend the day skiing on the surrounding slopes before relaxing in a hot spring, while in the warmer months, hiking through the highlands offers another way to enjoy the area’s spectacular scenery.
For travelers seeking a quieter side of Japan’s famous hot spring and mountain culture, Happo Onsen offers a fascinating glimpse into the history and natural character of Shiga Kogen.