Hawthorne Reef, located off Two Harbors, offers a varied topography ranging from 3 to 21 metres. This site is suited for advanced divers due to moderate currents and the requirement for boat access. Visibility typically ranges between 5 and 10 metres. Divers may encounter California sea lions, harbour seals, and various nudibranchs including Spanish shawls, Hermissenda, and clown dorids. Other observed life includes scorpionfish, sea stars, red gorgonians, and zoanthids. Given the entanglement risk at this site, carrying a cutting tool is recommended. Water temperatures fluctuate between 15 and 19 degrees Celsius throughout the year, necessitating appropriate thermal protection.

Underwater Arch in Two Harbors is a shallow site featuring a distinct rock arch formation. Divers can explore this structure at depths ranging from 1 to 7 metres. The site is accessible only by boat and is suitable for beginners due to the mild currents. Visibility at the site typically ranges between 5 and 10 metres. Water temperatures fluctuate throughout the year, reaching a high of 19C in the summer months and dropping to 15C during the winter. This site offers a straightforward profile for those looking to experience a unique geological feature in the waters of Santa Catalina Island.

Long Point is a shore-accessible reef and kelp forest site located near Two Harbors. The topography ranges from 5 to 35 metres, with an average depth of 20 metres. Divers should be prepared for mild currents and visibility between 5 and 20 metres. Entry requires a timed approach to navigate the shore break, surge, and sharp rocks. The site is suitable for intermediate divers and supports night diving. Hazards include potential entanglement in kelp, significant depth profiles, and rip currents. Facilities at the site include parking, showers, and toilets. Typical dives last approximately 45 minutes.

The Jenny Lynne is a wreck dive located 366 metres off the coast of Two Harbors, Santa Catalina Island. Resting at depths between 41 and 46 metres, this site is reserved for advanced divers experienced in managing decompression obligations. Visibility is limited to approximately 5 metres, necessitating precise navigation and compass work. Divers must remain vigilant regarding nitrogen narcosis and potential entanglement hazards posed by the wreck structure. Access is exclusively via boat charter. Given the depth and conditions, divers should maintain strict gas management and carry a surface marker buoy to ensure a safe ascent and recovery.

Old Marineland is a marine site located near Two Harbors, featuring a combination of reef, kelp forest, and pinnacle topography. Divers and snorkellers access the site via a shore entry, with the area extending approximately 274 metres from the coast. Depths range from 5 to 18 metres, with an average depth of 12 metres. Conditions are suitable for intermediate skill levels, though visitors should be aware of potential hazards including boat traffic, surf, surge, and thermoclines. Visibility typically fluctuates between 3 and 9 metres. Facilities available at the location include parking, toilets, showers, and a cafe.

Terranea Point near Two Harbors on Santa Catalina Island features a combination of reef and kelp forest environments. Divers and snorkellers can expect depths ranging from 5 to 21 metres, with an average depth of 10 metres. Access is via a shore entry, and the site is suited for intermediate skill levels due to moderate currents and potential surf. Typical dives last approximately 45 minutes. Visibility at the site generally fluctuates between 5 and 9 metres. Facilities available at the location include parking, toilets, showers, a rinse station, and a cafe. Hazards to be aware of include entanglement in kelp, sharp reef structures, strong currents, and surf conditions.

Christmas Tree Cove in Two Harbors offers a varied underwater landscape featuring reef, kelp forest, and wall terrain. Divers can explore depths ranging from 1 to 24 metres, with an average depth of 12 metres. The site is accessed via a shore entry, which requires caution due to a surf break and potential surge. With visibility typically between 3 and 4 metres and moderate currents, this site is suited for intermediate divers who can manage buoyancy and navigation in changing conditions. Water temperatures remain between 14 and 17 degrees Celsius throughout the year, necessitating appropriate thermal protection. Parking is available on-site, though spaces fill quickly on weekends.

Honeymoon Cove in Two Harbors offers a shore-entry dive featuring a combination of reef and kelp forest topography. Divers can explore depths ranging from 5 to 30 metres, with an average depth of 15 metres. Visibility typically spans 10 to 20 metres, and currents are generally mild. The site is suited for intermediate divers, though surge and swell conditions vary. Water temperatures range from 14 to 17 degrees Celsius, necessitating the use of a wetsuit. Divers should remain aware of boat traffic near the shore and exercise caution regarding sea urchins and sharp rocks when entering or exiting the water.