Hong Island—known locally as Koh Hong—anchors a protected archipelago 45 kilometres northeast of Phuket's eastern coast, where vertical limestone cliffs plunge into the Andaman Sea and shelter a tidal lagoon accessible only through a narrow rock corridor at high tide.
The island sits within Than Bok Khorani National Park, gazetted in 1991 to preserve 121 square kilometres of mangrove forest, coral reefs, and karst formations shaped by 260 million years of tectonic uplift and monsoon erosion. The national park conservation fee—300 baht per foreign adult as of 2026—supports reef monitoring and waste removal across the archipelago's 13 named islands.
Phang Nga Bay's fame rests on its drowned river valleys, flooded when sea levels rose eight thousand years ago and leaving behind more than a hundred limestone towers, some rising 200 metres above the waterline. James Bond Island, seven kilometres south of Hong, became a circuit anchor after The Man with the Golden Gun filmed there in 1974, but Hong's interior lagoon—a collapsed sinkhole fringed by mangrove roots and accessed by sea canoe—offers a quieter geology lesson. The lagoon floor drops to 12 metres at its deepest point, and at low tide the entrance passage narrows to three metres, rendering it impassable for larger vessels.
Most Hong Island tour from Phuket options depart Royal Phuket Marina or Ao Po Grand Marina between 08:00 and 09:00, crossing open water in 35-seat speedboats that cover the distance in 50 minutes. Operators pair Hong with neighbouring Panak Island, where collapsed cave systems create paddleable tunnels lit by fissures in the karst ceiling, and Lawa Island's sand spit, submerged at high tide. The route typically includes a midday pause at Panyi Island, a stilted Muslim fishing village built over the reef in the late 18th century by Javanese traders. Tour schedules align with tidal windows—morning departures target the lagoon entrance at mid-tide, when water depth permits canoe passage but currents remain manageable. Return crossings to Phuket conclude by 16:30, before the national park's daily closure.
9 hr
