Shukuba-no-yu is on Route 17 between Yuzawa and Naeba. It is in a little township called Futai that is at the base of the Tashiro Ropeway. Shuba-no-yu is a nondescript brown building just before the long hill up to Naeba and you can easily drive past without noticing it. However it is well worth a stop. There is a cozy little onsen run by the town, a small art gallery and a delicious ramen restaurant that also serves Thai food.
The onsen is everything you could wish for - clean, cheap, and really warm. It is within walking distance of the car park for the Tashiro Ropeway so if you fancy a warming dip after checking out the autumn colors or after a chilly day on the ski slopes, you are in luck.
The art gallery is dedicated to the work of a Niigata-born illustrator, Shiro Kawakami, who is famous for his works for children's publications. He also did many drawings related to the Buddhist monk Ryokan-sama who lived in Niigata prefecture. His drawings are really colorful and a delight to look at after a long, relaxing soak.
There's plenty to do at Shukuba-no-yu making it a worthwhile stop if you are heading up Route 17 or even as a side trip if you are spending time in Yuzawa.