Green Island, located off Cathedral Cove, is a diverse marine site featuring a combination of reef, cave, wall, and pinnacle topography. Divers can explore drop-offs ranging from 10 to 25 metres, with an average depth of 18 metres. Access is strictly by boat, as the site lies 8 kilometres from the shore. Conditions vary, with moderate currents and visibility typically between 10 and 30 metres. Hazards include surge, strong currents, and potential entanglement. Species recorded around this area include wrasses, green moray, long-nosed fur seal, eagle ray, common Sydney octopus, scorpionfish, snake eel, pink snapper, tube worm, crab, goatfish, sea hare, and sea star.

Peachgrove Bay, located near Cathedral Cove, features reefs at both ends of the bay. This marine site is accessible only by boat, situated 8 kilometres from the shore. Divers and snorkellers can explore depths ranging from 2 to 15 metres, with an average depth of 10 metres. Conditions are generally mild with visibility fluctuating between 4 and 20 metres. The water temperature varies seasonally from 15C to 22C. Suitable for beginners, the site offers a typical dive duration of 50 minutes. As a reef environment, it provides a habitat for general marine life, though specific species are not recorded for this location.

Never Fail is a reef and pinnacle site located at Cathedral Cove, New Zealand. This site is suited for advanced divers due to the presence of strong currents. The topography consists of a reef and pinnacle structure with an average depth of 15 metres. Access to the site is by boat only. Divers should be prepared for variable conditions and exercise caution regarding the strong currents present in this area. No specific marine life data is available for this location.

Coralie Bay, located near Cathedral Cove, features extensive kelp forest and reef systems interspersed with white sand patches. This marine site is accessible only by boat, situated 8000 metres from the shore. Divers and snorkellers can expect depths ranging from 15 to 30 metres, with an average of 20 metres. Conditions are variable, with mild currents and visibility typically between 5 and 10 metres. The site is suitable for intermediate divers and offers a 5/5 rating for snorkelling. Species recorded around this area include long-nosed fur seals, common Sydney octopus, eagle rays, wrasses, clown doris, snake eels, sea hares, sea stars, pink snapper, tube worms, crabs, goatfish, deepwater burrfish, and blue maomao.

Stanley Island, located near Cathedral Cove, offers a shallow marine dive experience with a depth of approximately 7 metres. The site is subject to variable conditions, and divers should be aware of the presence of strong currents in the area. Water temperatures fluctuate throughout the year, ranging from 15C in the winter months to 22C during the peak of summer. Due to the nature of the currents, this site is best suited for divers who are comfortable managing changing water movement. Access to the site is typically by boat from the surrounding Coromandel region.

The Bookcase at Cathedral Cove is a wall and reef dive featuring a straight wall that drops to a sandy bottom. Divers can typically circumnavigate the rock formation in a single dive. The topography includes long cracks and crevices along the perimeter, with interesting rock formations located around the inside corner. Depths range from 5 to 25 metres. Access is by boat only, and the site is suited for intermediate divers due to moderate currents and potential surge, particularly on the corner closest to Great Mercury. Visibility at the site varies between 10 and 30 metres, with water temperatures ranging from 15C to 22C throughout the year.

Old Man Rock, located off Cathedral Cove, offers a combination of open reef and cave diving. The site features depths between 15 and 30 metres with visibility ranging from 10 to 30 metres. Divers encounter an overhead environment within the cave sections, which requires precise buoyancy control and careful air management. Due to the depth and the nature of the terrain, this site is suited for intermediate divers with an Advanced Open Water certification. Access is by boat only, and divers should be aware of potential surface chop that can affect re-boarding. A torch is recommended for navigating the cave sections.

Crayfish Bay at Cathedral Cove features rocky ledges and extensive kelp forests. This marine site offers depths ranging from 2 to 13 metres, with an average of 8 metres. Snorkellers can observe a variety of marine life, including snails, which are very common, alongside uncommon sightings of Common Sydney Octopus, Red Comb Star, abalone, Pink Snapper, and crabs. Rarer species such as the Knobbed Triton, tube worms, and bluebottles are also recorded. The site is accessed from the shore and is suitable for intermediate snorkellers. Divers and snorkellers should be aware of moderate currents, potential surf, and boat traffic in the area.