Marine Club Sa-Wes Yonaguni
マリンクラブ サーウェス与那国DiveYonaguni-jima
Marine Club Sa-Wes is the Yonaguni dive shop of Kihachiro Aratake, who found the island's underwater ruins in 1986, and it dives the hammerhead sites from November to May, with two boat dives at ¥17,000 in 2026.
Kihachiro Aratake found the rock terraces of the Kaitei Iseki in 1986, and his shop has guided divers over them ever since. He also captains the boat that takes non-divers out to see them. The dive staff are all from Yonaguni. At the site the shop calls Hammerhead Rock you hold on to the reef and wait for the sharks to come past.
If you don't dive, the Jack's Dolphin semi-submersible reaches the ruins in 18 minutes from Kubura and seats you below the waterline for about an hour. Phone ahead, because it needs five adults to sail and runs at noon. The shop takes dive bookings by email at iriedonan4792@gmail.com.
What they offer
| Offering | From | Duration | Months |
|---|---|---|---|
| Boat dives2026 cash prices including tax: one dive ¥11,900, two dives ¥17,000, three dives ¥23,000, extra dive ¥6,600. Full rental ¥6,050, a 5 mm wetsuit ¥1,100. | ¥11,900 / person | One to three dives | Year-round; the shop lists November to May as hammerhead season |
| Underwater ruins experience dive2026 cash price including tax. | ¥31,000 / person | – | Year-round, weather permitting |
| Jack's Dolphin semi-submersible to the underwater ruinsPrices since May 2023: child (3 and up) ¥4,000, junior-high and high-school students ¥5,000, 65 and over ¥6,000. Sails from Kubura port at 12:00 with five or more adults; 18 minutes to the ruins. No hotel pickup at present. From June to September south wind can keep the boat off the ruins, and it shows the north coast instead. | ¥7,000 / adult | About 1 hr | Year-round, weather permitting |
FAQ
Quick answers about Marine Club Sa-Wes Yonaguniよくある質問
When is hammerhead season on Yonaguni?
Marine Club Sa-Wes lists November to May as the hammerhead season on Yonaguni. Water is 22–23 °C from January to March, and the shop recommends a 5 mm suit then.
Can you see the Yonaguni underwater ruins without diving?
Yes. Sa-Wes runs the Jack's Dolphin semi-submersible from Kubura port at 12:00, about an hour long, for ¥7,000 per adult. It sails with five or more adults and can skip the ruins when the summer south wind blows.
How much does diving cost on Yonaguni?
Marine Club Sa-Wes charges ¥17,000 for two boat dives and ¥23,000 for three in 2026, cash, with full rental gear at ¥6,050. Its underwater ruins experience dive costs ¥31,000.
Does Marine Club Sa-Wes Yonaguni speak English?
Marine Club Sa-Wes Yonaguni works in Japanese.
Is Marine Club Sa-Wes Yonaguni open in winter?
Marine Club Sa-Wes Yonaguni: Sa-Wes marks November through May as hammerhead season, with water at 22–23 °C from January to March, and the shop advises a 5 mm two-piece or one-piece suit for those months. Dress for 15–18 °C on land, with a sweatshirt or windbreaker and long trousers. The underwater ruins sit off the south coast, and the shop's own warning about wind is for the summer south wind.