Boston Harbor in Cape Ann offers a varied underwater environment featuring reefs, wrecks, and artificial reefs suitable for intermediate divers. The site requires boat access and is subject to moderate currents and variable visibility ranging from 5 to 25 metres. Depths at this location extend from 10 to 70 metres, with an average depth of 45 metres. Due to cold water temperatures between 4C and 12C, a dry suit is required in winter, while a 7mm wetsuit with a hood is recommended during summer months. Divers should remain vigilant regarding boat traffic, entanglement risks, and potential surf conditions.

Nahant Beach in Cape Ann offers a diverse underwater topography featuring reefs, canyons, caverns, and pinnacles. This shore-entry site is suitable for beginners, with depths ranging from 3 to 14 metres and an average depth of 8 metres. Divers should be prepared for cold water temperatures between 4 and 16C, alongside moderate currents and variable visibility of 6 to 9 metres. Hazards include surf, surge, rip currents, and potential entanglement. The site provides parking and toilet facilities for visitors. Typical dives here last approximately 50 minutes. Due to the presence of caverns and overhead environments, divers should maintain appropriate training and awareness of their surroundings.

Halfway Rock is a boat-access site located 1609 metres off Cape Ann, featuring a diverse topography of reef, wall, and pinnacle structures. The site ranges in depth from 15 to 30 metres, with visibility typically between 5 and 15 metres. Divers must be prepared for moderate currents, surge, and cold water temperatures ranging from 4 to 15 degrees Celsius. A thermocline is present, with temperatures below 15 metres often remaining near 10 degrees Celsius. Due to the depth and conditions, this site is suited for intermediate divers. A dry suit or thick wetsuit with hood and gloves is essential year-round to manage heat loss.

The City of Rockland is a shallow wreck located in Cape Ann, United States, resting at depths between 2 and 5 metres. This site is suitable for beginner divers, offering a mild current and visibility ranging from 5 to 15 metres. Divers should be aware of surf and shore break conditions during entry. Due to the wreck structure, entanglement is a potential hazard, and buoyancy control is essential. Water temperatures fluctuate significantly throughout the year, ranging from 4C to 19C, necessitating appropriate thermal protection. Typical dive times at this location are approximately 40 minutes.

Salt Rock is a shallow reef site located off Cape Ann, offering a consistent depth of 6 to 7 metres. This site is suitable for beginner divers, featuring mild currents and visibility ranging from 5 to 10 metres. Access is strictly by boat. Water temperatures fluctuate significantly throughout the year, ranging from 5C in winter to 18C during the summer months. Divers should plan for thermal protection, such as a drysuit or a 7mm wetsuit, particularly outside the warmer summer season. Species recorded around this area include harbor seals, gray seals, wrasses, common lobsters, sea ravens, pufferfish, horseshoe crabs, pipefish, various crabs, common sea stars, temperate bass, righteye flounder, and shrimp.

Paddock Rock is a pinnacle and wall site located 1207 metres off the coast of Cape Ann. This advanced dive site features significant depths ranging from 15 to 90 metres, with an average depth of 60 metres. Divers must access the site by boat. Conditions are variable, with visibility typically between 15 and 50 metres and moderate currents. Due to the depth, strong currents, and potential surge, this site is strictly for advanced divers. Water temperatures are cold, ranging from 4C to 9C throughout the year. Typical dive times are approximately 60 minutes.

Great Egg Rock is a reef and drop-off site located off Cape Ann. The site features depths ranging from 6 to 11 metres, with an average depth of 9 metres, making it suitable for beginner divers. Visibility typically ranges between 5 and 10 metres. Access is by boat only, and divers should remain vigilant for active boat traffic when surfacing. Water temperatures are cold, fluctuating between 5 and 17 degrees Celsius throughout the year. Divers must wear appropriate thermal protection, such as a 7mm wetsuit, hood, and gloves, to mitigate the risks associated with cold water conditions.

White Beach in Cape Ann is a shallow reef site suitable for beginner divers. The area features depths ranging from 6 to 7 metres, with an average of 8 metres. Shore entry requires caution due to potential surf, surge, and sharp rocks or coral; hard-soled booties are recommended. Visibility typically ranges between 5 and 8 metres, and currents are generally mild. The site is accessible year-round and supports night diving. Divers should remain aware of boat traffic and manage exposure risk in cold water, which fluctuates between 5C and 18C throughout the year. Facilities including parking, toilets, showers, and a rinse station are available on-site.