Japan Guide
Shikoku
Shimanto-gawa
Often claimed to be the last free-flowing river in Japan, the Shimanto-gawa actually has one small dam along its 196-kilometre length. This doesn't detract from the wide river's beauty, twisting through green countryside past pine-clad slopes and terraced rice fields, splashed with scarlet higanbena flowers in September. This is the place to head for tranquil boating, canoeing and fishing. Local fishermen still use a traditional method to catch ayu fish, waving flaming torches to coax them into waiting nets.
As a base, you can't go far wrong with the charming 
Shimantogawa Youth Hostel ( 
0880/54-1352, 
www.netwave.or.jp/~shimanto ; Price: ¥3000-5000), run by a friendly couple and about as far off the beaten track as you could wish for. It sleeps fifteen people, has good food and a regular programme of canoeing trips down the river (from ¥5500, full tuition and equipment included). The nearest train station is Ekawasaki on JR's plodding Yodo line, which runs from Kubokawa on the bay side of Kōchi-ken, to Uwajima along a very scenic route. From March to November it's possible to ride in open-air carriages (torroko ressha) for part of the route on most weekends and holidays and almost all of August. From Ekawasaki you'll need to catch a bus (Mon– Sat, three daily) to Kuchiyanai, from where the hostel is 4.5km across the river; if you call the hostel manager he will arrange to meet you. There are also a few buses to Kuchiyanai from Nakamura, on the Tosa Kuroshiro train line to Sukumo, but again not on Sunday.