Gab Gab in Tumon Bay, Guam, offers a diverse underwater environment featuring a reef, a wall, and an artificial reef. Divers can explore depths ranging from 5 to 30 metres, with an average depth of 18 metres. Access is via a shore entry, making it suitable for beginners. Conditions generally feature mild currents and visibility between 9 and 30 metres. The site is also available for night diving, with typical dives lasting 45 minutes. Facilities including parking, toilets, showers, and equipment rental are available. Species recorded around this area include Napoleon Wrasse, Emperor Angelfish, various wrasses, and Pacific Bullethead Parrotfish. Be aware of hazards such as boat traffic, entanglement, overhead environments, and sharp coral.

Gab Gab II is a large reef mound located within Apra Harbor, Guam. Situated approximately 91 metres from the shore, the site features depths ranging from 13 to 30 metres with an average of 20 metres. Divers and snorkellers can access the reef by boat or from the shore. Conditions are generally mild, with visibility between 10 and 30 metres. The site is suitable for beginners and supports night diving. Facilities available at the location include parking, toilets, showers, changing rooms, and a rinse station. Be aware of boat traffic in the area. A typical dive lasts 45 minutes.

Vecky's Reef is a marine site located within Apra Harbor, Guam. The site features a consistent depth of approximately 9 metres, though depths in the surrounding area can reach 20 metres. Access to this location is by boat only. Divers and snorkellers should be aware of moderate currents and potential boat traffic in the vicinity. Visibility at the site typically ranges between 12 and 21 metres. Water temperatures are warm throughout the year, ranging from 28C to 30C. This site is suitable for beginners, provided they are comfortable with the prevailing current conditions.

Barracuda Rock in Apra Harbor, Guam, is a diverse site featuring a reef, cavern, and tunnel system. The topography includes a mini cave and a tunnel beneath a large coral head, providing swim-throughs suitable for beginners. Depths range from the surface to 32 metres, with an average depth of 14 metres. Access is by boat only. Divers and snorkellers should be aware of potential hazards, including overhead environments, sharp coral, and mild currents. Visibility varies significantly, ranging from 9 to 45 metres. Water temperatures remain warm throughout the year, typically between 28 and 30 degrees Celsius.

San Luis Beach in Apra Harbor, Guam, offers a combination of natural reef and artificial reef structures accessible via a shore entry. The site is suitable for beginners, with depths ranging from 6 to 33 metres and an average depth of 18 metres. Divers should anticipate mild currents and visibility typically between 6 and 10 metres. The location is well-equipped with facilities including parking, toilets, showers, changing rooms, and rinse stations. Air fills, dive shops, and boat charters are available nearby. Night diving is permitted at this location. Hazards to be aware of include jellyfish, rip currents, sharks, sharp coral, and stonefish.

Blue Hole in Apra Harbor is a natural limestone plateau featuring a vertical shaft that begins at approximately 18 metres and opens through a window at 38 metres. This site offers a varied topography including a wall, reef, drop-off, and cavern environment. Depths range from 10 to 95 metres, requiring advanced certification and deep diving experience to navigate the shaft. Visibility typically spans 10 to 40 metres, though divers must account for potential strong currents, surge, and boat traffic. Access is strictly by boat. Due to the significant depth and overhead environment, this site presents hazards including nitrogen narcosis and decompression requirements.

SeaBee Junkyard in Apra Harbor is an artificial reef site featuring a collection of heavy equipment, including bulldozers, abandoned by the Seabees following the construction of the breakwater. The site also contains a small transfer ship resting on the seabed at a depth of 40 metres. Divers can explore this underwater industrial site at depths ranging from 11 to 40 metres, with an average depth of 14 metres. Access to the site is by boat only, located 183 metres from the shore. Conditions include moderate currents and visibility ranging between 6 and 18 metres. Water temperatures remain consistent throughout the year, typically between 28 and 30 degrees Celsius.

The American Tanker is a concrete barge located in Apra Harbor, Guam, originally used to transport fuel during World War II. This artificial reef sits at depths ranging from 8 to 36 metres, with an average depth of 25 metres. The wreck is accessible only by boat and is suited for intermediate divers due to the overhead environment. Divers should be aware of boat traffic in the area. Visibility typically ranges between 6 and 18 metres, and water temperatures remain consistent between 28 and 30 degrees Celsius throughout the year. The site offers a unique opportunity to explore historical maritime remains in a marine environment.