Japan’s deepest lake, Tazawa-ko (Lake Tazawa), and the traditional town of Kakunodate are good side-trips into Tohoku's wilder interior, approachable from either Morioka or the west-coast city of Akita. For a little thermal relaxation in a very rustic setting, forge on to the old spa town of Nyuto Onsen, just north of Lake Tazawa. Accessible by bus from Tazawa-ko are several small, unspoiled, mountain hot-spring spas.
Most of these have only one inn, and you'll have to take your meals there. It's advisable to arrange accommodations before you arrive if you plan to stay the night, and the Tazawa-ko Tourist Information Office can help arrange this.