Green Island at Rottnest Island features a combination of natural and artificial reef structures. The site ranges from shallow depths to 37 metres, with an average depth of 15 metres. Access is by boat, as the site is located 2000 metres from the shore. Divers and snorkellers should be prepared for moderate currents and visibility between 10 and 30 metres. Hazards include sharp coral, jellyfish, and variable currents. Beginners are advised to remain in the shallower sections of the reef. Facilities including a dive shop, toilets, showers, and a cafe are available nearby.

Rottnest Island features a diverse underwater landscape consisting of walls, caves, reefs, drop-offs, and a wreck. Accessible only by boat, the site offers depths ranging from 2 to 26 metres with an average of 10 metres. Divers should be prepared for moderate currents and variable visibility between 3 and 30 metres. Water temperatures fluctuate between 19C and 23C, with cold currents and thermoclines possible at North Point. Hazards include boat traffic, jellyfish, surf, surge, and strong currents. The site is suitable for intermediate divers, with facilities available for air fills, equipment rental, and guided tours. Night diving is permitted, and typical dive times are approximately 50 minutes.

Salmon Bay on Rottnest Island provides a sheltered shore entry point suitable for beginners and snorkellers. The site features a diverse underwater landscape of reef and seagrass habitats, with depths ranging from 1 to 12 metres. Protected by offshore reefs, the bay typically offers calm conditions, though mild currents may be encountered further from the shore. Visibility generally fluctuates between 5 and 15 metres. Water temperatures remain between 19C and 23C, influenced by the Leeuwin Current. Toilets are available at the site for visitor convenience. Users should remain aware of potential surf conditions during entry and exit.

The City of York is a historic wreck located 200 metres offshore at Rottnest Island. Resting in shallow waters between 4 and 9 metres deep, this site is suitable for beginners. Divers explore the wreck structure and surrounding reef, which feature sponges and various marine life including crayfish, Western Blue Devil, Western Dhufish, Western King Wrasse, and Australian Giant Cuttlefish. Conditions are generally manageable with a mild current, though visibility varies significantly from 3 to 20 metres depending on weather. Boat access is required to reach the site. Divers should exercise caution regarding sharp coral and potential entanglement hazards within the wreck structure, while also monitoring surf conditions before entry.

Little Armstrong Bay on Rottnest Island offers a sheltered shore entry dive suitable for beginners. The site features a reef and cave topography with depths ranging from 6 to 7 metres, averaging 4 metres. Divers benefit from mild currents and visibility typically between 15 and 20 metres. Water temperatures fluctuate between 19C and 23C, necessitating appropriate thermal protection year-round. The bay is protected from waves and winds, providing a stable environment for underwater exploration. Divers should remain aware of potential boat traffic in the area. Conditions are most settled during the spring and autumn months.

Porpoise Bay at Rottnest Island features a combination of sheltered reef and a cave system. This boat-accessible site ranges in depth from 8 to 20 metres, with an average of 15 metres. Visibility typically spans 15 to 30 metres. The site is suitable for beginners, though the cave represents an overhead environment requiring careful buoyancy control and guidance. Divers should remain aware of potential currents, which can be stronger than at other local sites, and watch for boat traffic upon entry. Water temperatures range from 19 to 23C, influenced by the Leeuwin Current.

Mickey Mouse and Maze is a complex reef, wall, and canyon system located off Rottnest Island. The site features a series of caves and swim-throughs that create overhead environments, requiring divers to be comfortable with confined spaces. Depths range from 1m to 27m, with an average of 15m. Visibility typically spans 15m to 30m, assisting with navigation through the intricate structure. Access is by boat only, and conditions generally feature mild currents. Hazards include boat traffic, jellyfish, and sharp coral. Divers should carry a torch and line cutter to manage the overhead sections safely. Guided tours and air fills are available locally.

Duffield Ridge is a boat-access reef and cave site located 1500 metres off Rottnest Island. Designed for advanced divers, the site features depths ranging from 17 to 30 metres with an average of 26 metres. Divers navigate moderate currents and visibility typically between 5 and 10 metres. The topography includes reef structures and caves that provide shelter for various marine life. Be prepared for thermoclines and sudden temperature drops, which can occur even during summer months. Due to the depth and current, this site requires careful planning and close buddy contact throughout the dive.