「We stayed at Oohira hotel in October to use it as a base for hiking. It is perfectly located, near the top end of Zao Onsen, right next to the base of the mountain and the big Zao outdoor onsen. We found it with no issues, and the hotel will pick you up from the bus station if you call in advance.
The main thing to stand out for us at Oohira was the staff, who were really excellent throughout. They even spoke some English which was surprising and welcome!
The hotel building itself is a little...
