Marine House Seasir, Aka Island, Okinawa

Marine House SEASIR is a long-established dive operation in Okinawa, Japan, providing access to the reefs of the Kerama Islands. The company operates from two distinct bases: one in the city of Naha on Okinawa’s main island, and another on Aka Island within the Kerama archipelago itself. Each branch offers a slightly different diving rhythm, depending on whether guests prefer city convenience or island proximity.

The Naha branch operates as a structured day-boat dive centre, transporting divers to Kerama sites each morning. The Aka Island branch, located inside the marine park, offers shorter boat rides and a more immersion-focused island setting. Both operate under PADI 5-Star standards and provide guided diving, training and introductory programs.

Resort Facilities & Meals

Marine House SEASIR functions primarily as a dive operator rather than a full-service resort. In Naha, guests typically stay in nearby hotels, with easy access to restaurants and urban amenities. On Aka Island, accommodation is located close to the dive base, offering a quieter setting and walking-distance access to boats and beaches. Meals are generally arranged locally depending on branch and booking style.

Activities

Scuba diving and snorkelling form the core of operations at both branches. Introductory dives are available for beginners, while certified divers join scheduled boat trips. On Aka Island, additional time may be spent exploring beaches or coastal trails between dives.

Staying Connected

Wi-Fi access is available at accommodation facilities and nearby establishments, depending on location. Connectivity is suitable for general communication and travel coordination.

We Think . . .

Marine House SEASIR is best suited to divers who want professional, structured diving within a protected marine park. Travellers who prefer convenience and transport links may favour the Naha base, while those seeking shorter boat rides and a more contained dive-focused environment may prefer Aka Island.

Marine House SEASIR operates in Okinawa Prefecture, southern Japan. Diving takes place primarily within the Kerama Islands, a designated marine national park located west of Okinawa’s main island. The region is known for stable water temperatures, coral reef ecosystems and seasonal encounters with turtles and pelagic species.

From Naha, dive boats reach Kerama dive sites in approximately 40–60 minutes depending on conditions. The Aka Island branch reduces travel time further, with many sites located within short boat rides of the harbour.

How to Get There

Marine House SEASIR Naha is located in Naha, approximately 10–15 minutes by taxi from Naha Airport.

To reach the Aka Island branch, guests travel from Tomari Port in Naha by high-speed ferry to Aka Island. Transfers from the island port to accommodation are arranged locally.

Naha Branch

Divers using the Naha branch of Marine House SEASIR typically stay in nearby city hotels within central Naha. This arrangement provides easy access to restaurants, convenience stores and public transport while maintaining scheduled daily departures to the Kerama Islands. Accommodation is urban in style, suited to travellers who prioritise logistical convenience and airport proximity.

Aka Island Branch

On Aka Island, accommodation is located within walking distance of the Marine House SEASIR dive facilities. Rooms are simple, functional and designed around a dive-focused schedule rather than resort luxury. The setting is quieter and more self-contained than Naha, allowing divers to remain close to the harbour and boats. This setup is suited to guests who prefer shorter boat transfers and a marine park environment over city amenities. There are three room types at the guest house: Single Tatami Rooms, Double/Twin Share Tatami Rooms and Twin/Triple Share Western Style rooms.

First Floor Western Rooms with shared facilities.

Private ensuite Japanese style rooms.

Western Style ensuite rooms with wooden flooring and three single beds.

Check-in 16:00
*You can leave your belongings at the reception before check-in.
Check-out 10:00
*You can leave your belongings at the reception after check-out.
Pick-up service Transfers to and from Aka port can be arranged for free upon request.
Free facilities and amenities include Towels, shampoo and soap, hair dryers, kettles, cups, toothbrushes, razors and other sanitary goods.
*Fridges can be found in the common space.
Facilities and amenities not included in room charges Washing machine (JPY 200 per wash)
Drying machine (JPY 100 per use)

Diving Location Features

The Kerama Islands are known for clear water, stable temperatures and coral reef diversity. Visibility frequently exceeds 20 metres in favourable conditions. Reef terrain includes coral slopes, sandy patches, rock formations and moderate drop-offs. Sea turtles are regularly sighted, and seasonal shifts may bring additional pelagic activity.

Dive Services

Marine House SEASIR operates as a certified PADI 5-Star dive centre across both branches. Guided boat dives, beginner programs and continuing education courses are available. Daily schedules are organised according to sea conditions and diver experience, typically offering two or three dives per outing.

Boats are configured for day operations, with structured briefings conducted before each dive. Equipment rental is available, and groups are arranged to maintain manageable ratios and consistent supervision.

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Diving with Marine House SEASIR provides access to more than 50 identified sites throughout the Kerama Islands. Site selection varies by branch departure point, sea conditions and diver experience level, offering a mix of relaxed coral dives and occasional drift-style environments. Highlights of the Kerama Islands include Triple Stones – three large bommies simply teeming with life and Kuba West – a large pinnacle that’s great fun to circle around as you swim slowly to the top.

• Sand Triangle – A sandy-bottom site known for frequent turtle sightings. Calm conditions and moderate depth make it suitable for divers of varied experience levels.
• Kuroshima Twin Rocks – A reef structure featuring vertical elements and schooling fish activity. Light to moderate currents may be present depending on tide.
• Toma No. 2 – A combination of coral and sand terrain offering gentle profiles and steady reef fish presence, often selected for introductory or second dives.
• Gishippu West – A coral-rich site with varied structure and moderate current potential, suitable for intermediate divers.
• Zamami Area Reefs – Reef formations with healthy coral growth and open water exposure, occasionally attracting larger fish species.

Pricing for Marine House SeaSir