This marvellously secluded place is in a wooded dell 7km northeast of Kappa-bashi. It's both a campground (¥700 per person) and a lodge, and has capsule-style dorm rooms, Japanese-style rooms (with shared facilities), and hearty meals served in a busy dining hall. There's a nice bath, a cafe and a small shop. Access is by walking only (about two hours).
Tokusawa-en
Top choice in Matsumoto & the Northern Japan Alps