This Onsen Ryokan has various types of rooms, and we stayed in the Garden Wing, which is a separate building with very basic accommodations but at a very reasonable price. The Garden wing is also rather cumbersome to reach from the main lobby.
The main building has the roten-buro outside bath, which was nice. Breakfast was also nice and service very friendly.
The area is beautiful mountain scenery with a lake and a breathtaking waterfall 20min walk away. The village however only has accommodations but no stores or restaurants, and after dark it is dead. This is a great place for hiking, or if one has a car to escape the heat of lower lying areas. When Tokyo had 35deg Celsius, Okunikko had 19 in summer.