From Joubon no sato we took a rather dog-leg route (a road was closed and we had to go the wrong way before turning round) north towards Ichinoseki and the Genbe-kei Gorge. Once there we bought boat tickets (¥1600 apiece, £12) for a big punt with about a dozen other customers to be poled up the river between towering cliffs and accompanied by ducks, fish (sweetfish locally) and huge carp about a yard long all begging for food. The pole-man also sang a song which you can hear on the video below.
The trip lasted about 75 minutes (including a short walk where the water is too fast and rough for the punt) and was a delight.
We then drove to the Gebekei Gorge michi no eki which is quite a distance from that gorge, and much closer to Genbikei Gorge which appears to be just over the road. There are onsens close by which we may investigate.
After a quiet night we walked to Genbikei gorge - and found it was only about 500m along a path and then we crossed a rather ancient suspension bridge which swayed alarmingly but provided excellent views of the splendid little gorge.
There was an interesting service for visitors - you could order food and drink from the café across the gorge by putting ¥400 in a basket and banging a board with a hammer. The basket would then be pulled back across the gorge to the café, filled with cups of green tea and a box of sweetened rice cakes, and lowered back across the gorge again to the waiting customers. There were lots of people taking advantage of this service.