[Access] Approx. 15 minutes by car from Komoro IC on the Joshinetsu Expressway
[Website] Shinshu Komoro Hishino Onsen Yakushikan (Japanese)

After finishing my hike to Mt. Kurofu to see the ‘gateau chocolat’ Mt. Asama, my main plan was a day trip to Takamine Onsen, the ‘Lamp Inn’ (Japanese). But unfortunately, their day-use hot spring closed much earlier than scheduled that day. So, I started looking for another good onsen on my way home and stumbled upon Hishino Onsen.

After driving down from the Mt. Asama trailhead for a while, Hishino Onsen quietly appears in a spot where you’d wonder if there really is a hot spring here. It seems there are two inns here, Yakushikan (Upper Bath) and Tokiwa-kan (Lower Bath), but I didn’t realize that at the time and just headed for Yakushikan. Stepping inside, there was a hall with gleaming polished wooden floors, and a gentle-mannered young couple welcomed me. Perhaps reflecting their tastes, the place was adorned with many retro and playful items, creating a unique atmosphere quite different from the quiet surroundings outside.

The bathroom has three bathtubs arranged in a stepped layout, and you enter from the changing room directly into the largest, uppermost tub. While I sometimes see this kind of layout in outdoor baths (rotenburo), I feel it’s quite uncommon for indoor baths (uchiyu). Entering the bathroom, there’s a faint scent of hydrogen sulfide, and the hot spring water had slightly orange-tinted “yu-no-hana” (mineral deposits), with a subtle hint of iron.

First, I stepped into the uppermost tub, which was probably around 41 degrees Celsius. It was chilly outside, so it warmed me up perfectly. After I was thoroughly warm, I moved to the middle tub, and as expected, it was a lukewarm bath. It was quite a mild temperature, almost as if they were gradually adding warm water from the upper tub. This kind of bath is so relaxing, you might just doze off if you’re not careful!

Finally, I moved to the lowest tub, where the water was overflowing generously, and when I dipped my foot in, I was shocked! It was intensely cold. There were obvious mineral deposits around the spout, so I had just assumed it was hot water, but it turns out it was a free-flowing “cold spring” with a temperature of 14 degrees Celsius. Since I was already there, I tried hard to submerge my lower body, but I couldn’t imagine getting in up to my neck…

When you put your cold body from the cold spring into the warm bath, it feels like your whole body is tingling with stimulation. I figured with these kinds of tubs, you’re probably supposed to alternate between them, so I went back and forth a few times. And indeed, according to the inn’s explanation, “By repeating the alternating baths about 5 times, you can experience the so-called ‘totonou’ state (a feeling of deep relaxation and invigoration).”

The hot spring quality at Hishino Onsen is a simple hot spring, with a total mineral content of 561 mg/kg, pH 7.04, and a cold spring temperature of 14.3 degrees Celsius. While it might not seem particularly distinctive by numbers, it has a unique aroma and orange-colored “yu-no-hana” (mineral deposits). Personally, I felt like I had discovered a really great hot spring! If I get the chance, I’d love to stay overnight.