Kochi Prefecture is known for mountains, forests and above all, rivers. On the Niyodo River, we learn a special technique for catching sweetfish so good they're mostly bought by exclusive Kyoto restaurants. We climb a steep hillside to meet a couple who irrigate their organic farm with pure mountain springwater. Historically, the highest-grade charcoal came from Kochi's oak forests, and we meet its leading charcoal maker, a man who builds his own kilns and plants new forests for the sake of future artisans.