Koh Bida Nok is a diverse dive site located in the Racha Islands, Thailand, offering a mix of reef, wall, and cavern topography. Divers can explore depths ranging from 3 to 30 metres, with an average depth of 18 metres. Access is strictly by boat, as the site is situated 2000 metres from shore. Conditions vary, with visibility between 5 and 25 metres and moderate currents. The site is suited for intermediate divers. Hazards include potential entanglement, jellyfish, overhead environments, sea urchins, sharp coral, stonefish, and strong currents. The habitat supports a variety of reef fish and invertebrates typical of the region.

Hin Daeng is a remote pinnacle and wall system located 70 kilometres from shore. The site features a dramatic drop-off with depths ranging from 5 to 60 metres, averaging 25 metres. Due to the exposed location, divers encounter strong currents and potential surf, making this an advanced dive site. Visibility varies between 10 and 30 metres. Water temperatures typically range from 26C to 29C, though thermoclines can create cooler layers at greater depths. Access is strictly by boat, and dives typically last 60 minutes. Divers must be prepared for deep diving conditions, including the risks of decompression and nitrogen narcosis.

Koh Racha Noi offers diverse topography including reefs, walls, pinnacles, and drop-offs. The site features a shallow bay ranging from 3 to 10 metres, suitable for training, while the outer sloping reef extends to depths of 30 metres. Accessible only by boat, the site is suited for intermediate divers due to moderate currents and potential down currents. Visibility typically ranges from 10 to 40 metres, though thermoclines can occasionally affect clarity. Water temperatures remain warm, averaging between 28 and 30 degrees Celsius. Species recorded around this area include various reef fish, moray eels, and triggerfish. Divers should be aware of deep water and strong currents.

South Tip at Koh Racha Noi is a challenging drift dive site consisting of a series of pinnacles extending south from the island. The topography includes a wall and reef structure that reaches depths between 9 and 50 metres, with an average depth of 20 metres. Due to strong currents, down currents, and the potential for decompression requirements, this site is strictly for advanced divers. Access is by boat only. Visibility varies significantly, ranging from 5 to 40 metres. Divers should be prepared for deep diving conditions and the associated risks of nitrogen narcosis.

Racha Noi Bay features a diverse underwater landscape comprising reefs, drop-offs, pinnacles, and artificial structures. Located off Koh Racha Noi, the site offers depths ranging from 5 to 30 metres with an average of 20 metres. Visibility typically spans 10 to 30 metres, though thermoclines may occasionally reduce this. While currents are generally mild, strong currents and down currents can develop rapidly near drop-offs and pinnacles. Divers should remain close to their guide and monitor depth closely. Access is by boat only, and the site is suitable for beginners, though conditions require attention to briefings. Species recorded around this area include peacock mantis shrimp, Indian lionfish, and various triggerfish.

Ray Bahn is a deep reef site located at Koh Racha Noi, Thailand, characterised by its significant depth and challenging conditions. The reef structure drops from 23 to 40 metres, with an average depth of 20 metres. Divers must be prepared for strong, shifting currents that require careful air management and advanced diving skills. Visibility typically ranges between 10 and 30 metres, and water temperatures remain between 28 and 30C, though regular thermoclines occur. Access is by boat only, and the use of a reef hook is recommended to maintain position against the flow. Due to the depth and current, this site is strictly for advanced divers.

Aussie Reef at Koh Racha Noi is a drift dive site featuring hard corals in the shallows and deep coral bombies. The site offers depths ranging from 3 to 30 metres, with an average depth of 15 metres. Access is by boat only, as the site is located 24 kilometres from shore. Divers should be prepared for moderate currents and variable visibility between 10 and 30 metres. Due to the potential for strong currents, surf, and deep water, this site is suited for intermediate divers. Water temperatures remain consistent throughout the year, typically between 28 and 30 degrees Celsius.

South Tip at Koh Racha Noi offers a varied underwater landscape featuring a wall, pinnacle, and artificial reef. This boat-access site ranges from 3 to 25 metres in depth, with an average of 15 metres. Visibility typically spans 10 to 40 metres. Divers should be prepared for moderate currents, which can shift quickly and occasionally produce downward pulls. Due to these conditions, the site is best suited for experienced divers who can manage depth and drift. Species recorded around this area include various lionfish, triggerfish, moray eels, and groupers. Always confirm current conditions with your boat captain before descending and plan your dive around slack water when possible.