Koh Yipun

Ko Yipun is a small, uninhabited island in the Kam Islands group, part of Laem Son National Park off Suk Samran district in Ranong — not, as the name might suggest, part of Koh Phayam, which sits about 27km further north. Its draw is hard coral reef in the shallows and a white-sand beach on the island’s east side, reached only by chartered longtail boat.

Locals originally knew the island as Koh Man Marong, after a wild yam the Moken sea-gypsies once dug here. The current name — “Japan Island” — is usually traced to a group of Japanese pearl farmers who worked the waters afterward, though some local accounts instead point to a wartime Japanese base; neither story is definitively confirmed. Either way, the island itself is compact and hilly, ringed by hard coral where clownfish and other reef fish shelter among the branching structures. Snorkelling straight off the beach is the main activity — there’s no jetty infrastructure or dive shop, just clear water and a stretch of sand backed by forest.

Because Ko Yipun has no permanent population and no facilities, it works only as a day trip, usually bundled with neighbouring islands like Koh Kam on a longtail tour out of Suk Samran or Hat Bang Ben. Laem Son National Park, which the island falls under, charges its standard entry fee — 200 THB for foreign adults, 40 THB for Thai nationals — which boat operators typically add to the cost of the trip rather than including it upfront.

Visit November through April for the calmest seas and clearest water; the rest of the year sits inside the Andaman monsoon window, when crossings get rougher and visibility drops. Early morning departures give the best light for snorkelling before afternoon wind picks up.

Insider Tip: Ask your boat operator whether the Laem Son park fee is included in the quoted price — it often isn’t, and turning up short of cash on an uninhabited island is a bad surprise.

Watch out: there’s no shade, food, or drinking water available on the island itself — pack everything you need for the day, including reef-safe sunscreen.