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
- Mon–Fri 11:00–21:00 (last entry) / weekends, holidays & peak days 11:00–15:00 and 19:30–21:00 (last entry)
- Closed
- Open daily (entry limits in peak season)
- 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
- Admission
- Day bathing: adults (junior high+) ¥1,650 / children (3–12) ¥825 / under 3 free. Special periods (Golden Week, summer, New Year) ¥1,760/¥880. Towels not included — bath and face towel rental set ¥330. Private rotenburo ¥4,070 per 45 min (sea side ¥4,620). Relaxation-plus-half-price-bath packages available
- Baths
- 'Yuya Umi-no-Kairo', a bathhouse right on Kamogawa's Matsubara beach — a semi-outdoor 'yuya' modelled on the lattice of a Japanese room, a Pacific-view rotenburo and lie-down bath, sauna and jacuzzi. Two indoor and two outdoor baths per side, three private rotenburo. The 'Garden Bath', an outdoor rock bath of bakuhan stone, is in a separate wing
- Water
- Kamogawa Onsen 'Nagisa-no-yu' — a sulphur-bearing sodium chloride-bicarbonate cold mineral spring (hypotonic, mildly alkaline). The rare pairing of sulphur and bicarbonate leaves skin smooth; heated and recirculated. On water-change days some baths open only from 14:00
- Parking & access
- Free parking. Free 5-min shuttle from Awa-Kamogawa Station on the JR Sotobo Line (about 15 min on foot). About 2 h from Tokyo Station on the 'Wakashio' limited express, or about 2 h by the 'Aqcy' highway bus via the Aqua-Line. About 50 min from Kimitsu IC on the Tateyama Expressway via Routes 410 and 128
- Phone
- 04-7092-2111
- Official site
- kgh.ne.jp ↗
- Open in Google Maps
- Google Maps ↗
Essentials
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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
A window full of sea — sulphur-tinged 'Nagisa-no-yu' at a resort hotel on Kamogawa's Matsubara beach
Kamogawa Grand Hotel is a large resort hotel standing directly on Matsubara beach in Kamogawa, Chiba — the Sotobo coast's signature swimming beach — and, paired with Kamogawa Sea World five minutes away, a fixture of family trips from the Tokyo area. Its spring, 'Nagisa-no-yu', is a sulphur-bearing sodium chloride-bicarbonate cold mineral spring, an unusual combination of sulphur and bicarbonate that leaves skin smooth. The bathhouse 'Yuya Umi-no-Kairo', designed around the lattice and corridor motifs of a Japanese room, is semi-outdoor: you can cool off in the sea air to the sound of waves, then slip straight into the Pacific-facing rotenburo or lie-down bath. With two indoor and two outdoor baths per side, sauna and jacuzzi, three sea-side private rotenburo and a bakuhan-stone rock bath called the 'Garden Bath', it is large for a hotel spa. Day bathing (¥1,650) is generous on weekdays, 11:00–21:00, but at weekends and in peak season it splits into afternoon and evening sessions with possible entry limits, so time your visit. A free five-minute shuttle from Awa-Kamogawa Station, two hours from Tokyo by the 'Wakashio' express or the Aqua-Line highway bus — one of the easiest sea-view onsen day trips there is.
Tips & notes
① Weekends, holidays, long weekends, summer, Golden Week and New Year run in two sessions — 11:00–15:00 (last entry) and 19:30–21:00 — with no entry between 15:00 and 19:30. ② Special periods cost ¥1,760 and entry may be limited when busy. ③ Towels not included (rental ¥330) — bring your own to save. ④ On water-change days some baths open only from 14:00; phone (04-7092-2111) before a morning visit. ⑤ The sea-side private rotenburo is the popular one — book ahead. ⑥ The sulphur smell is faint but may still tarnish silver. ⑦ The Awa-Kamogawa shuttle runs to a fixed timetable — check it at the front desk.
Getting there
From Tokyo Station, the JR Sotobo Line 'Wakashio' limited express reaches Awa-Kamogawa in about 2 h (roughly hourly), or take the 'Aqcy' highway bus via the Aqua-Line from Tokyo Station or Yokohama, about 2 h — then the hotel's free 5-min shuttle from the station or bus stop (15 min on foot). By car: Aqua-Line → Kimitsu IC on the Tateyama Expressway → Routes 410 and 128, about 50 min, about 1 h 40 min from central Tokyo; free parking. Combine with Kamogawa Sea World (5 min), the Oyama rice terraces and Seichoji temple for an overnight, or do it as a Tokyo day trip. Other inns near the station, such as Maruki Honkan's 'Nagisa-no-yu' (¥1,000), also take day bathers if you want to compare.
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 Operating status and rates cross-checked against the official site and onsen guides (full source notes in Japanese on the JA page)
Prices and hours change. Check official sources before visiting.
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