Trio Island, located off South Ninepin Island, features a combination of natural reef and artificial reef structures. The site ranges in depth from 5 to 21 metres, with an average depth of 10 metres. Divers encounter mild currents, though conditions can vary, and visibility typically spans 5 to 15 metres. Access is strictly by boat, and the site is suitable for intermediate divers. Due to active boat traffic in the area, divers must deploy a surface marker buoy before ascending and remain vigilant during safety stops. The site is also suitable for night diving, with typical dives lasting around 45 minutes.

Little Palm Beach on Shelter Island provides a shallow reef environment ideal for beginner snorkellers. The site features depths ranging from 2 to 6 metres, with an average of 4 metres. Conditions are generally mild, though visibility fluctuates between 3 and 10 metres. Shore entry is straightforward, but users should remain cautious of boat traffic near the entry point, particularly on weekends. Toilets are available at the location. When entering the water, be mindful of sharp coral and potential hazards on the seabed. Maintain neutral buoyancy to avoid contact with the reef surface and stay aware of your surroundings throughout your session.

Shelter Island in Hong Kong offers a shallow reef environment suitable for beginners, with depths ranging from the surface down to 9 metres. The site is accessible only by boat, and the mild currents make it a manageable location for snorkelling. Water temperatures fluctuate between 19C and 29C throughout the year, requiring appropriate thermal protection during cooler months. Visibility is variable and depends heavily on local weather, tidal movements, and seasonal changes. Due to active boat traffic in the area, snorkellers must remain vigilant when surfacing and are advised to use a brightly coloured snorkel vest or tow float for visibility.

Pak Shui Wun is a shore-entry snorkel site located at Shelter Island, Hong Kong. The site features a shallow reef structure ranging from the surface to 4 metres in depth, making it suitable for beginners. Water temperatures fluctuate between 19 and 29 degrees Celsius throughout the year. While the current is generally mild, snorkellers should remain vigilant for boat traffic in the area. Visibility at the site is variable. Species recorded around this area include nudibranchs, lionfish, dragonets, anemonefish, butterflyfish, wrasses, puffers, rock cod, and banded coral shrimp.

South Ninepin Island offers a shallow reef environment suitable for beginner divers. The site features a reef structure extending from the surface to a maximum depth of 12 metres. Access is exclusively by boat, and the area typically experiences mild currents. Visibility at this site can vary significantly, so divers should check local conditions before departure. Water temperatures fluctuate between 19 and 29 degrees Celsius throughout the year, requiring seasonal adjustments to exposure protection. Divers must remain vigilant regarding active boat traffic in the vicinity and avoid contact with the seabed to prevent injury from sharp rocks and coral.

Kwo Chau Wan at South Ninepin Island offers a diverse underwater landscape featuring reefs, caves, caverns, and drop-offs. Divers can explore these formations at depths between 7 and 15 metres. Conditions typically involve moderate currents and a visibility of 5 metres, requiring careful navigation. Due to the presence of sharp coral, rocks, and sea urchins, precise buoyancy control is essential. Boat access is required to reach this site, which is located 14 kilometres from shore. Divers must remain vigilant regarding boat traffic and are advised to deploy a surface marker buoy at all times to ensure visibility during the dive and ascent.

Basalt Island, located near East Ninepin Island, features a reef environment suitable for beginners and snorkellers. The site ranges from the surface to a maximum depth of 13 metres. Divers frequently encounter Zebra Lionfish, Flamingo Tongue, and Clark's Anemonefish. Other species recorded here include Robust Ghost Pipefish, Chromodoris Nudibranch, Stonefish, Indian Lionfish, Scorpionfish, White-spotted Puffer, Flatworm, Pufferfish, Rock Cod, Starry Puffer, and various wrasses. Access is by boat only. Conditions, including visibility and current, are variable. Due to active boat traffic in the Sai Kung area, divers must deploy a surface marker buoy before ascent and remain aware of their surroundings.

East Ninepin Island is a reef dive site in the Ninepin Group of Hong Kong, offering depths reaching 14 metres. The site is suitable for beginner divers looking to gain experience on reef terrain. Access is exclusively by boat, and divers should be aware that currents are variable and visibility can shift between visits. Due to the presence of sharks in the area, divers must remain alert during descents and ascents, keep bodies streamlined, and avoid trailing loose equipment. Boat traffic is common, so the use of a dive flag and surface marker buoy is essential. Ensure all equipment and air fills are prepared before departure.