This incredibly picturesque, meandering river is marked by cascading waterfalls, carved-out gorges and gurgling rapids. Walkers can follow its path for a 14km stretch connecting Nenokuchi, on the eastern shore of the lake, to Yakeyama, from where relatively frequent buses return to either Nenokuchi (¥610, 30 minutes) or the main lakeside tourist hub of Yasumiya (¥1130, one hour).

The entire hike should take about three hours. Set out in the early morning or late afternoon to avoid slow-moving coach parties.