Maintop Island is a reef site located off the Pacific Coast near San Francisco. Divers typically encounter depths between 15 and 18 metres with visibility ranging from 10 to 30 metres. The site is accessible by boat and features mild currents, though conditions vary. Marine life includes California sea lions, Northern elephant seals, Steller sea lions, and harbor seals. Divers may also spot great white sharks, ocean sunfish, various nudibranchs, and jellyfish. Due to water temperatures of 10 to 12 degrees Celsius, a drysuit or 7mm wetsuit with hood and gloves is recommended. Hazards include boat traffic, surge, and sharp rocks; monitor local conditions before entry.

Hurst Shoal is a reef dive located off the Pacific Coast near San Francisco. The site sits at depths between 14 and 18 metres and is noted for visibility reaching 30 metres. Divers access the reef by boat, where they encounter moderate currents that require careful positioning. Due to water temperatures ranging from 11 to 13 degrees Celsius, appropriate thermal protection such as a drysuit or thick wetsuit is essential for all divers. The site is suitable for beginners looking to build experience in Pacific Coast conditions. Always confirm boat access arrangements and check locally for current site conditions before planning a dive.

Middle Farallon is an advanced open-ocean dive site located 48 kilometres off the coast of San Francisco. The topography consists of a reef, wall, and drop-off structure ranging from 8 to 17 metres in depth. Divers must navigate challenging conditions, including strong currents, heavy surge, and visibility fluctuating between 3 and 10 metres. Water temperatures remain cold, typically between 11 and 13 degrees Celsius, necessitating appropriate thermal protection. Access is strictly by boat due to hazardous surf conditions at the shore. Given the exposure to open Pacific waters, this site requires high situational awareness and careful planning around slack water to manage currents effectively.

Isle of Saint James is a reef site located off the Pacific Coast near San Francisco. Divers access this location by boat to explore depths ranging from 25 to 35 metres. Visibility is consistently 30 metres, though the water remains cold at 9 to 11 degrees Celsius. While currents are generally mild, the site is subject to significant surges and requires careful buoyancy control. Due to the depth and cold, a drysuit or thick wetsuit with hood and gloves is necessary. Species recorded around this area include California sea lions, northern elephant seals, Steller sea lions, harbour seals, great white sharks, ocean sunfish, sea nettles, jellyfish, nudibranchs, scorpionfish, sea stars, crabs, and snails.

Noonday Rock is a deep offshore pinnacle located 45 kilometres from the coast near San Francisco. The site features a dramatic profile, with depths ranging from 20 to 120 metres and an average depth of 70 metres. Due to the significant depth and strong currents, this site is strictly for advanced divers. Visibility typically ranges between 10 and 30 metres, with water temperatures consistently between 8 and 9 degrees Celsius. Boat access is required, and divers must be prepared for challenging conditions, including strong currents and the presence of sharks. Species recorded around this area include California sea lions, Northern elephant seals, Steller sea lions, harbour seals, and great white sharks.

Fanny Shoal is a reef and pinnacle site located 64 kilometres offshore from San Francisco. This advanced dive site features depths ranging from 6 to 40 metres, with an average depth of 25 metres. Divers must use a boat for entry due to significant surf at the shore. Conditions are challenging, with strong currents and visibility fluctuating between 3 and 18 metres. Water temperatures remain cold, between 9 and 13 degrees Celsius, requiring appropriate thermal protection. Given the depth and current, divers should monitor their profile closely and time their visit to slack water. Hazards include deep water, strong currents, surf, and the presence of sharks.

Fitzgerald Marine Reserve is a shallow rocky reef system in the United States, primarily accessed from the shore. The site features a flat reef topography with an average depth of 3 metres, ranging between 1 and 5 metres. Conditions are variable, with hazards including low visibility, surf, and strong currents. Divers and snorkellers frequently encounter harbour seals, ochre sea stars, rock crabs, and northern kelp crabs. Various nudibranchs are also present, including common clown dorids and san diego dorids, alongside less frequent sightings of east pacific red octopuses and white-spotted sea goddesses. Due to the challenging conditions, this site is suited for advanced divers.

Heart's Desire Beach on the Pacific Coast is a sheltered location featuring seagrass beds. It is suitable for beginners due to the lack of waves and mild currents. The water is generally warmer than the open Pacific, though temperatures remain cool, ranging from 12C to 16C throughout the year. Visibility is lower than in other coastal areas. Access is via a shore entry, and the site provides facilities including parking, toilets, and showers. Snorkellers should be prepared for cool water conditions.