For a town so closely associated with water, it's rather fitting that Gujo-Hachiman is shaped like a fish.

"An ayu (sweetfish), to be exact," clarifies Yuka Tanaka, my guide for the afternoon and a native of this small town of approximately 18,000 inhabitants tucked away in the mountains of Gifu Prefecture. "Ayu need clear water to thrive, and we have plenty of that in Gujo-Hachiman."

The town sits at the confluence of four rivers: the tiny Otohime and the Kodara, which both flow into the mighty Yoshida. Together, all three join the Nagara River to the west of town.