The Aldermen Islands, located 20 kilometres off the coast of Whitianga, offer diverse underwater topography including reefs, pinnacles, walls, and caves. Divers can explore depths ranging from 8 to 40 metres, with an average depth of 20 metres. Access is strictly by boat. Conditions are variable, with visibility typically between 15 and 30 metres and water temperatures fluctuating from 15C to 21C throughout the year. The site is suitable for beginners, though divers should be aware of potential hazards including deep water, variable currents, and low visibility. Species recorded around this area include wrasses, blue maomao, eagle rays, green moray, sea stars, snails, and chromis.

Mooring Bay is a reef dive site located on the Coromandel Peninsula, offering a straightforward experience for newly certified divers. The site features an average depth of 9 metres, with a range of 8 to 10 metres. Visibility typically spans 5 to 10 metres. Access is by boat only, requiring coordination with a local dive shop. Divers should be prepared for water temperatures between 15 and 22 degrees Celsius, making a wetsuit necessary. Hazards include potential surge and swell, sea urchins, and sharp rocks on the reef. Always remain alert to surface boat traffic and deploy a surface marker buoy during ascents.

Whenuakura Island features a collapsed volcanic blowhole that creates a sheltered lagoon. Access to this interior space is via a narrow sea cave located on the south-eastern side of the island. Situated 600 metres from the shore, the site requires boat access and is rated highly for snorkeling. Conditions vary, with moderate currents and potential surf near the entrance. Water temperatures fluctuate between 15C and 22C throughout the year. Species recorded around this area include long-nosed fur seals, eagle rays, common Sydney octopus, green moray, wrasses, clown doris, southern rock lobster, snake eel, scorpionfish, pink snapper, blue maomao, goatfish, crabs, and deepwater burrfish.

Onemana Northern Rocks is a shore-entry snorkeling site located at the northern end of Onemana Beach near Whitianga. The site features a series of rocky inlets and reef structures that provide a local alternative to busier coastal areas. Conditions at this site vary, and snorkelers should be aware of potential surf and rip currents in the area. Water temperatures range from 15C to 22C throughout the year. Due to the nature of the entry and potential water movement, this site is best suited for intermediate snorkelers. Parking and toilet facilities are available near the beach access point.

Hapuka Rock is a pinnacle and wall site located off the coast of Whitianga. The formation rises from a depth of 25 metres on the ocean side and 20 metres on the western end to a shallow point of 5 metres. This site is exposed to easterly and southerly swells and wind, resulting in variable currents and surge. Due to these conditions and the depth, it is recommended for intermediate divers. Access to the site is by boat only. The topography features steep walls that provide a distinct underwater profile for exploration.

Russ' Ravine is a diverse marine site featuring a reef, wall, pinnacle, and cavern system. The topography includes a rock formation that rises to 8 metres at its shallowest point, with the surrounding seabed reaching depths of 28 metres. Divers can explore an excellent swim-through, with ample areas available for those preferring to stay shallower than 18 metres. The site is sheltered from north and west winds, though conditions require intermediate skill due to potential hazards including boat traffic, cold water, and strong currents. Access is by boat only, with an average dive depth of 15 metres.

Spectacle Reef near Whitianga is a diverse site featuring a combination of reef, pinnacle, and wall topography. Divers can explore depths reaching 20 metres, making it suitable for beginners. Access to the site is by boat only, and divers should remain aware of boat traffic in the area. Conditions are generally mild, with water temperatures ranging from 15C to 22C throughout the year. The site offers a varied underwater landscape for those looking to explore the coastal features of the Coromandel region.

Mahurangi Island, located 100 metres off Hahei Beach near Whitianga, offers a diverse marine environment featuring reefs and kelp forests. The site is suitable for beginners, with depths ranging from 2 to 18 metres and an average depth of 5 metres. Divers and snorkellers can expect mild currents and visibility that varies significantly between 1 and 25 metres. Shore access is available, and the site supports both day and night diving. Facilities at the nearby shore include parking, toilets, showers, changing rooms, a cafe, and a dive shop offering guided tours. Water temperatures fluctuate between 15C and 22C throughout the year.