2026 Full-Day Course: Naokawa Ikoi-no-Mori Park River Pool (直川憩の森公園 河川プール)

This one-day course in Saiki City, Oita Prefecture, centers on the concrete-built Naokawa Ikoi-no-Mori Park River Pool (直川憩の森公園 河川プール), filled by damming and channeling water from the Akagi River (赤木川). The venue is Naokawa Ikoi-no-Mori Park (直川憩の森公園) in Naokawa, Saiki City, a park equipped with a management building called 'Papillon,' a 202-meter roller slide, and an Insect Museum, alongside the attached river pool. The river pool is officially scheduled to open on July 18 in 2026, with daily admission throughout the summer school holidays. Since the closing date has not yet been announced, check official information for late-summer plans. Because the pool uses river water directly, it's cold and clear, yet since it's built as a proper pool, the footing is stable — making it easy for even small children to play safely. There are shower buildings with two rooms each for men and women, which can also be used for changing clothes, keeping the trip home comfortable. Admission is an affordable 300 yen for kindergarten age and up, making it easy for families to spend a full day without worry. In the morning, get acquainted with the freshwater fish of the Bansho River at Michi-no-Eki Yayoi, then enjoy local flavors for lunch at Michi-no-Eki Naokawa. In the afternoon, finally head to the river pool and make the most of the water play during the sunniest hours.