Van Damme State Park on the Mendocino Coast offers a protected cove environment featuring a reef, kelp forest, and the Cave of the Trolls tunnel located on the north wall. This shore-entry site is suitable for beginners and provides depths ranging from 3 to 80 metres. Divers and snorkellers may encounter harbor seals, various crab species including northern kelp and rock crabs, sea stars, and nudibranchs like Hermissenda, clown dorids, and red sponge dorids. Ling cod, king crab, and egg-yolk jellyfish are also recorded here. Conditions include mild currents and visibility up to 50 metres, though surge and surf are present. Water temperatures remain cold, averaging 8 to 10 degrees Celsius throughout the year.

Jack Peters Cove on the Mendocino Coast offers dramatic rocky topography featuring several swim-throughs and arches. This site is suited for advanced snorkellers due to the challenging nature of the terrain and the deeper water compared to nearby locations. Access is via the shore. Water temperatures are cool, ranging from 11C to 14C throughout the year. The site provides a rugged environment for those experienced in navigating rocky reef and cavern structures. Conditions vary, so careful planning is required for entry and exploration of the underwater features.

Russian Gulch State Park features a distinctive W-shaped cove on the Mendocino Coast. Divers and snorkellers enter from a sandy beach located directly beneath the Frederick W. Panhorst Bridge. The site consists of rocky reef structures that provide protection from the open ocean. Depths range from 3 to 12 metres, with an average of 6 metres. Conditions are suitable for beginners, though the water is cold, ranging from 10 to 13 degrees Celsius, and a wetsuit is recommended. Divers should be aware of potential hazards including cold water, surf, and surge. Facilities at the park include parking, toilets, and showers.

Stornetta Cove is a shallow reef and kelp forest site located 500 metres off the Mendocino Coast. Divers and snorkellers typically experience depths between 5 and 6 metres, with an average depth of 5 metres. Visibility is generally around 5 metres, providing intimate conditions for exploring the kelp environment. The site is suitable for beginners, as there is no significant current to manage. Water temperatures remain cool, ranging from 11 to 13 degrees Celsius throughout the year. Access requires a boat, and visitors should be prepared for potential surf, surge, and swell conditions. A thick 7mm wetsuit or a drysuit is strongly recommended for comfort in these cold waters.

Arena Cove on the Mendocino Coast offers a shore-entry reef and kelp forest experience at depths between 15 and 18 metres. The site is characterised by cold, nutrient-rich water ranging from 10 to 12 degrees Celsius, requiring appropriate thermal protection. Divers and snorkellers may encounter common species such as Northern Kelp Crabs, Ochre Sea Stars, and various snails. Uncommon sightings include East Pacific Red Octopuses, Monterey Dorids, Ling Cod, and Leather Stars. Visibility varies from 5 to 15 metres. Due to surf, shore break, and potential rip currents, this site is suited for intermediate divers. Always remain vigilant for boat traffic and use a surface marker buoy.