Chiba · Kamogawa Onsen
Kamogawa Grand Hotel – Umi no Kairō Baths
鴨川グランドホテル 湯屋 海の回廊（日帰り入浴）
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.
- Price (adult)
- ¥1,650
- Hours
- 11:00–22:00 (weekends, holidays & busy days: 11:00–15:30 / 19:30–22:00)
- Closed
- Open daily (entry limits when crowded)
- Access
- About 5 min by shuttle bus or car from Awa-Kamogawa Station (JR Sotobō Line); about 40 min by car from Kimitsu IC via the Kamogawa toll road; about 15 min on foot from Kamogawa Sea World
- Water type
- Simple spring
- Tattoos
- Ask ahead
- Phone
- 04-7092-2111
- Official site
- www.kgh.ne.jp/04/plan/dayuse.html ↗
- Open in Google Maps
- Google Maps ↗
Essentials
Stay in this onsen town
Compare and book stays in Kamogawa Onsen. Day bathing itself needs no booking.
Opens partner booking site (affiliate)
Why go
- Ocean-view open-air bath facing the Pacific horizon
- Day bathing at a resort near Kamogawa Sea World
- ¥1,650; 11:00–22:00 weekdays, split hours weekends
Before you go
- No official tattoo policy is published — ask at reception.
- Ryokan day-use hours are limited and may be suspended in peak season — phone the same morning.
- Last entry is 30–60 minutes before closing.
Features
Sauna & wellness
Mood & scenery
Price
Who with
Amenities
✔ Verified operating: 2026-09 公式サイト（大人1,650円 小人825円・特別期間1,760円・通常11–22時 受付21:00・繁忙日二部制・タオル別330円）／ちば観光ナビ（無休）
Prices and hours change. Check official sources before visiting.
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