Kurokawa-So

An absolutely wonderful experience.
The staff at the ryokan were incredibly polite and always ready to help with anything we needed. Upon check-in, we were provided with traditional attire, pajamas, tabi slippers, bath amenities, and a small welcome treat with matcha and coffee. We also asked at the front desk if they could give us a ride to the bus stop after check-out, and they kindly said yes, of course. 
Our room was spacious, clean, and beautifully decorated. At first, we were planning to explore several other local onsens, but after experiencing the ones at the ryokan, we felt completely satisfied. There are separate baths for hotel guests (men’s and women’s), baths open to both guests and visitors (also divided by gender), as well as a private onsen. One of the onsens also has a sauna.
The traditional dinner and breakfast were both impressive—delicious and very generous in portion.
The surrounding grounds are stunning, perfect for peaceful walks. This ryokan is a bit further from the main cluster of inns, but that was exactly what we wanted—to enjoy quiet walking.
At night, our futons were laid out for us, adding to the authentic experience. The only reason I deducted one star is the very bright green light on the ceiling that stays on all night and can’t be turned off or covered. I didn’t have a sleep mask with me, and the ryokan didn’t provide one, so I had a sleepless night. It was quite unpleasant.
That said, I still highly recommend this ryokan—it’s an unforgettable place to stay.

Having a private onsen and the services were so good for dinner and introduction of village

Fantastic stay! Excellent room with open-air bath and little garden. Food tasted great, well balanced saltiness and sweetness. Service staff were warm and efficient, taking initiative to provide service for guest's convenience.

Great experience with nature hot spring and wonderful service