The USS San Diego is an artificial reef wreck located in the Long Island Sound. Resting at depths between 20 and 35 metres, this site is suited for advanced divers with wreck certification. Access is by boat only, situated approximately 21.7 kilometres from shore. Divers should be prepared for moderate currents and variable visibility ranging from 3 to 18 metres. Water temperatures fluctuate between 5°C and 18°C, necessitating a drysuit or a 7mm wetsuit with a hooded vest. Due to the depth and potential for nitrogen narcosis, careful bottom time management and redundant lighting are essential for navigating this challenging wreck.

Hylton Castle is a wreck site located in the Long Island Sound, requiring boat access due to its distance of 24 kilometres from the shore. This advanced dive site features a consistent depth of 30 metres. Divers should be prepared for moderate currents and visibility ranging from 3 to 15 metres. Water temperatures fluctuate between 5C and 19C, with warmer conditions occasionally influenced by the Gulf Stream during summer months. Hazards at this location include boat traffic, cold water, deep conditions, potential entanglement, strong currents, and sharks. Dives typically last around 30 minutes.

12 Mile Reef is an advanced dive site located in the open waters of the Long Island Sound. This site features a combination of wreck structures and artificial reef materials that reach depths of up to 38 metres. Due to the depth and variable currents, this location is suitable only for advanced divers. Water temperatures range from 5C to 17C, necessitating the use of a drysuit or thick wetsuit. Divers should be aware of significant boat traffic in the area and must deploy a surface marker buoy during ascent. Visibility is highly variable, and carrying a torch is recommended for exploring the structure.

Obi is a shallow shore dive located in Long Island Sound, suitable for beginner divers. The site maintains a consistent depth of approximately 3 metres. Water temperatures fluctuate significantly throughout the year, ranging from 5C in February to 24C in July. As a marine environment, the habitat supports a variety of temperate marine life, including various reef fish and invertebrates typical of the region. Due to the shallow nature of the site, it is accessible for entry directly from the shore. Divers should be prepared for variable conditions typical of this coastal area.

Democrat Point is an artificial reef located in the Long Island Sound. This site is suitable for intermediate divers, with an average depth of 5 metres. Access is available via both shore and boat entries. Divers should be prepared for variable conditions, including moderate to strong currents, surge, and low visibility. Hazards at this location include cold water temperatures, which can drop to 5C, as well as potential entanglement risks and rip currents. The habitat supports a variety of temperate marine life and invertebrates typical of the region. Parking facilities are available for visitors.

Shipwreck Cove in the Long Island Sound features a combination of a shipwreck and an artificial reef structure. Located 1609 metres from shore, the site sits at depths between 7 and 13 metres, with an average depth of 10 metres. Conditions are suitable for beginners, though divers must navigate mild currents and variable visibility ranging from 2 to 15 metres. Hazards include potential entanglement in wreckage, sharp edges on structures, and active boat traffic overhead. Divers should use a surface marker buoy upon ascent. Due to water temperatures fluctuating between 5 and 20 degrees Celsius, appropriate thermal protection is required, with drysuits or thick wetsuits recommended outside of the summer months.

The Mandy Ray Wreck is a deep-water site in the Long Island Sound reaching depths of 34 metres. This advanced dive requires boat access and involves navigating moderate currents and cold water temperatures ranging from 5 to 17 degrees Celsius. Divers must manage entanglement risks within the wreck structure and remain vigilant of active boat traffic during ascent. A surface marker buoy is essential for safety when surfacing. Due to the depth and thermal conditions, appropriate drysuit or heavy wetsuit protection is required. Species recorded around this area include gurnard, pufferfish, barracuda, spotfin butterflyfish, horseshoe crab, wrasses, groupers, toadfish, sea bass, crab, lizardfish, righteye flounder, common sea star, and temperate bass.

Ponquogue Bridge is a shore-accessible drift dive site located in Hampton Bays. The site features an artificial reef structure beneath and around the bridge, with depths ranging from 0 to 10 metres and an average depth of 5 metres. Divers should be prepared for strong currents and variable visibility between 2 and 10 metres. Due to the nature of the location, hazards include boat traffic, potential entanglement, and surf. This site is suited for intermediate divers, with typical dives lasting around 35 minutes. Parking and toilets are available, though seasonal parking permits are required for access.