Kamogawa Grand Hotel – Umi no Kairō Baths
The Umi no Kairō bathhouse of this large resort hotel on the Pacific shore of Kamogawa, on the outer coast of the Bōsō Peninsula, welcomes day visitors. Fed by Kamogawa Onsen, tapped in 2003, its open-air bath faces the ocean with an uninterrupted view of the horizon and breaking waves; there are also an indoor bath, sauna and a glass-walled lounge looking out to sea. Adults (junior-high age and up) pay ¥1,650 and children aged 3–12 ¥825, rising to ¥1,760/¥880 in peak periods such as Golden Week, summer and New Year. Towels are not included – rent a set for ¥330 or bring your own. Normal hours are 11:00–22:00 (last entry 21:00), but on weekends, holidays and busy days bathing is split into 11:00–15:30 and 19:30–22:00. Open every day, with entry limits when crowded, and day plans with spa treatments or lunch are available. About 5 minutes by shuttle or car from Awa-Kamogawa Station on the JR Sotobō Line, close to Kamogawa Sea World – a fine finish to a day at the beach.