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Diamond Setouchi Marine Hotel
forumWhat families say
Guests praise the Toy Kingdom rooms and the location right in front of Shibukawa Beach as things children love. The summer-only indoor heated pool and natural hot spring, Tamano Onsen, are also cited as reasons for its popularity.
Categories
Kids Facilities
Crib and portable bassinet rental
Crib and portable bassinet rental
Cribs and portable bassinets are available to rent for co-sleeping children for a fee of 1,100 yen. Quantities are limited, so advance contact before the stay is required.
- •The fee is 1,100 yen.
- •Advance contact with the hotel is required because quantities are limited.
Kids' area, Waku Waku Maze, and game area
Kids' area, Waku Waku Maze, and game area
The first-floor lobby has a kids' area and Waku Waku Maze, while the basement level 1 has a game area. These indoor play areas can be enjoyed by small children through elementary school-age children regardless of the weather.
Indoor heated pool, shallow children's pool, and Garden Water Park
Indoor heated pool, shallow children's pool, and Garden Water Park
- calendar_monthSeason:Summer only
The indoor heated pool is 20 meters long, 6 meters wide, and 1.2 meters deep, with an adjacent shallow pool for children under school age measuring 54 centimeters deep. In summer, the first-floor garden terrace also features the Garden Water Park with a water slide and animal boats. The pools operate only in summer.
- •Operations are limited to summer.
Family rooms supervised by Shibukawa Animal Park
Family rooms supervised by Shibukawa Animal Park
There are 4 types of family rooms supervised by Shibukawa Animal Park. The bright interiors feature animal illustrations and are so children can take off their shoes and play on the floor. They measure 66 to 85 square meters and accommodate from 2 to 8 guests.
Toy Kingdom rooms Hoshizora and Aozora
Toy Kingdom rooms Hoshizora and Aozora
The Japanese-Western rooms Hoshizora and Aozora are inspired by Toy Kingdom. They have a single bed and a double bed, with futons added for stays of 3 or more guests.
Festival and birthday plans
Festival and birthday plans
- calendar_monthSeason:Seasonal
A festival is held during Golden Week, and birthday plans include a Toy Kingdom all-day pass or a birthday plate, providing ways for families to celebrate a child's birthday.
Overview
A beach resort hotel facing Shibukawa Beach in Tamano, Okayama. It has a natural radon onsen with a communal bath and open-air bath, plus a 20-meter indoor heated pool, a shallow pool for children who have not yet started elementary school, and, in summer, the Garden Water Park. Four family-room types supervised by Shibukawa Animal Park, crib rentals, and a kids' area support family stays. Toy Kingdom and Shibukawa Animal Park are about 5 minutes away by car.
Rooms
The hotel offers 4 types of family rooms supervised by Shibukawa Animal Park. The bright interiors feature animal illustrations and are so children can take off their shoes and play on the floor. Options include the 66-square-meter Family Room, including 6 tatami mats; the 85-square-meter Yamagoya (Mountain Lodge), including 8 tatami mats; the 69-square-meter Mizube (Waterside), including 8 tatami mats; and the 60-square-meter Makiba (Pasture), including 12 tatami mats. The Mountain Lodge, Waterside, and Pasture accommodate from 2 to 8 guests, while the 66-square-meter Family Room accommodates from 2 to 6 guests. Japanese-style and Japanese-Western rooms require guests to lay out the futons themselves. There are also Japanese-Western rooms called Hoshizora and Aozora, inspired by Toy Kingdom. They have a single bed and a double bed, with futons added for stays of 3 or more guests.
Dining
Breakfast is a Japanese and Western buffet at the first-floor Restaurant Sunset, served from 7:00 to 10:00. Dinner is popular for its buffet of about 50 Japanese, Western, and Chinese dishes, with a teppanyaki station where chefs cook before guests and a chocolate fountain. Other options include a Korean barbecue restaurant serving authentic Korean cuisine and selected Japanese beef, as well as a Japanese restaurant featuring seafood from the Seto Inland Sea. Guests on plans without dinner can order from the affordable menu at Wa, the hotel's casual dining spot, including takoyaki, ramen, udon, and fried chicken. Child rates vary in detail by accommodation plan and age. For co-sleeping children ages 0 to 2, there is no meal charge; ages 3 to 4 may co-sleep with the meal fee only; and many plans from age 5 or 6 do not accept co-sleeping and instead charge a child rate including bedding and meals.
Baths and Onsen
The hotel has the natural radon onsen Tamano Onsen. The waters are a sodium-calcium chloride spring and a radon spring (known as ginsen, or “silver spring”). Facilities include a communal bath, open-air bath, and sauna. Depending on the date, morning bathing the following day may be unavailable because of communal-bath maintenance, so guests are advised to check their stay date. Children's yukata are available in sizes 120 cm to 160 cm, but only for guests staying under plans that include bedding and meals.
Play Areas and Pools
The first-floor lobby has a kids' area and Waku Waku Maze, while the basement level 1 has a game area. They can be enjoyed by small children through elementary school-age children. The indoor heated pool and shallow pool for children under school age, (54 cm deep) are open only in summer. The indoor heated pool is 20 meters long, 6 meters wide, and 1.2 meters deep. In summer, the first-floor garden terrace also features the Garden Water Park with a water slide and animal boats. Toy Kingdom and Shibukawa Animal Park are about 5 minutes away by car, while Naoshima, home to the Chichu Art Museum, is about 40 minutes away by car and ferry.
Family-friendly Features
Cribs and portable bassinets are available to rent for co-sleeping children for a fee of 1,100 yen. Quantities are limited, so please contact the hotel in advance. Humidifiers and air purifiers are also available to borrow, with limited quantities. A toilet for small children is available on the first floor. A festival is held during Golden Week, and birthday plans include a Toy Kingdom all-day pass or a birthday plate. Parking for 90 standard-size cars is available free of charge; when it is full, Shibukawa Tourist Parking, which is free for 21 hours, can also be used. Guests can extend checkout to 12 p.m. for an additional JPY 1,000 per person.
Access & Information
| location_onAddress | 2-12-1 Shibukawa, Tamano, Okayama 706-0028 |
|---|---|
| directions_carAccess | By car, about 25 minutes from Kojima IC on the Seto-Chuo Expressway via Route 430. By JR, get off at Okayama Station and take the bus bound for Tamano and Shibukawa from bus stop 2; get off at the last stop, which is right in front of the hotel. |
| trainNearest station | Kojima Station |
| local_parkingParking | Parking for 90 standard-size cars is free of charge, with no reservations and spaces available on a first-come, first-served basis. Shibukawa Tourist Parking is free for 21 hours and charged thereafter. |
| callPhone | +81-50-8882-2679 |
| paymentsCards | VISA, JCB, American Express, Diners Club, UFJ Card |
| languageOfficial site | https://www.marine-hotel.co.jp/open_in_new |
Reference price as of August 26, 2026 (stay date 2026-09-19). Please check the booking site for actual rates.
Frequently Asked Questions
Are cribs or portable bassinets available for co-sleeping children?
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Cribs and portable bassinets are available to rent for a fee of 1,100 yen. Quantities are limited, so please contact the hotel in advance.
Are the pools open all year?
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No. The indoor heated pool and shallow pool for children under school age operate only in summer. The Garden Water Park also appears in summer and has a water slide and animal boats.
What meals are available for children who co-sleep?
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For co-sleeping children ages 0 to 2, there is no meal charge. Ages 3 to 4 may co-sleep with the meal fee only. Many plans from age 5 or 6 do not accept co-sleeping and instead charge a child rate including bedding and meals.
Does the hotel have an onsen and communal bath?
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Yes. Tamano Onsen is a natural radon onsen with a communal bath, open-air bath, and sauna. The waters are a sodium-calcium chloride spring and a radon spring (known as ginsen, or “silver spring”).
How can we reach the hotel by public transportation?
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Get off at Okayama Station and take the bus bound for Tamano and Shibukawa from bus stop 2. Get off at the final stop, and the hotel is right in front of the stop.
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Information on this page was compiled by directly consulting Official website, Rakuten Travel, Jalan (last verified: August 2026). Prices, availability and seasonal operations change — please check each booking site for the latest information.
We take care to keep information accurate, but always confirm the latest details on the hotel's official site and booking sites before you book or visit.