Cold soba noodles rest on a round bamboo tray, served with dashi broth for dipping and a red tin of shichimi spice from Yawataya Isogoro (八幡屋礒五郎). Nagano is Japan's leading soba-producing prefecture: the cool mountain air and nutrient-rich soil of its highlands create ideal conditions for growing buckwheat. Kiso, Nagano Prefecture, Japan.