Koh Man Nok

Ko Man Nok is the outermost of the three islands in Rayong’s Mu Koh Man group, sitting furthest offshore from Mae Phim Beach — the order running out from the coast is Ko Man Nai, then Ko Man Klang, then Ko Man Nok. It earns its “Bird Island” nickname from the seabird colonies that nest along its cliffs and rocky shore. Entry is free, daily 08:00–17:00, and you pay only for the boat.

Despite what some listings claim, Ko Man Nok is not joined to Ko Man Nai by a sandbar — that tidal feature belongs to their neighbour Ko Man Klang. The two are separate islands roughly 15–30 minutes apart by speedboat, each reached independently from the mainland piers near Laem Mae Phim.

Of the three, this is the quiet one. Ko Man Nai has the sea turtle conservation project and takes most of the day-trip traffic; Ko Man Nok has the beach, the birds, and very little else. Snorkelling over the rocky edges reaches decent coral cover, with the clearest water from November through April when the Gulf is at its calmest.

Watch out: there are no facilities here — no restaurant, no shade shelter, no drinking water for sale, and no gear rental. Carry everything you need for the day, including reef-safe sunscreen and your own snorkelling kit.

Boats run from Pak Nam Prasae Pier or Ao Makampom Pier. Ko Man Nai is about 40 minutes out; Ko Man Nok is a further leg beyond it, so operators will usually only add it when the sea is calm enough for the extra crossing. Most trips combine two of the three islands rather than singling one out — ask before you book whether Man Nok is actually on the route that day.