Koh Bida Nok

Koh Bida Nok is a small limestone island with vibrant hard and soft coral gardens and steep underwater terrain, including dramatic walls covered in large sea fans and sponges. The site is known for abundant reef life and is particularly famous for regular sightings of blacktip reef sharks, zebra (leopard) sharks and hawksbill turtles. Dives are conducted by boat only. A common route follows the tall vertical wall on the north and often drifts toward the sheltered southern bay. Depths range from shallow coral plateaus around 3 to 5 meters up to about 28 to 30 meters on the wall. Visibility is usually good, often around 10 to 20 meters. Currents are variable - generally mild on calm days but can be moderate to strong along the wall, and many dives are planned as drift dives from north to south. The shallow bay suits open-water divers, while the deeper wall and potential for strong currents make some areas more appropriate for advanced divers. The island lies within a marine national park; only certified divers are permitted and try-dives and open-water training dives are prohibited.