VisitWakayama.jp The Official
Wakayama Travel Guide

Kawayu Onsen is one of the three hot spring hamlets that make up the Hongu Onsen-kyo area. It is conveninent to the Kumano Kodo trails and easily reached by bus from Kumano Hongu Taisha Grand Shrine. There are several hot spring hotels and ryokan with a variety of different baths in the area, but it is Senninburo, a large open-air bath in the middle of the Oto-gawa river, that really steals the show.