Umagai is a wall and reef site located off Aka Island, Japan, featuring a dramatic drop-off that descends from 7 metres to 40 metres. The site offers visibility between 20 and 30 metres, supported by moderate currents. Divers should exercise caution near the wall face, as surge can push swimmers toward sharp coral and rock edges. While the site is accessible to beginners, the significant depth requires careful buoyancy control and monitoring of depth gauges. Boat access is required for all dives. Protective gear is recommended to prevent injury from sharp substrate. Divers should consult with their boat operator regarding current conditions before entry to ensure a manageable experience.

Hate No Hama is a reef site located off Aka Island, accessible only by boat. The site features depths ranging from 8 to 15 metres with visibility typically between 10 and 30 metres. While suitable for beginners, the site is known for strong currents that can shift quickly, requiring divers and snorkellers to remain vigilant and consult with boat operators before entry. Water temperatures fluctuate between 22 and 29 degrees Celsius throughout the year. Divers should maintain neutral buoyancy to avoid contact with sharp coral and rocks, and remain aware of regular boat traffic in the area, particularly during safety stops.

Hatenohama, specifically the Naka-no-hama section, is a 7km sandbar composed of three islets. This site features white sand bottoms interspersed with coral patches, creating a shallow environment suitable for snorkelling. Depths typically range from 1m to 5m, with an average of 3m. Access is exclusively by boat, as the site is located 5km from the shore. Conditions vary, with visibility generally between 15m and 30m and moderate currents. Hazards include sharp coral and strong currents. Facilities available at the site include toilets, showers, and a dive shop. The site is rated 5/5 for snorkelling and is suitable for beginners.

Manta Station is a reef site located 4000 metres off Aka Island in the Kerama Islands. This site is primarily accessed by boat and is suitable for advanced snorkelers. The topography features a reef environment with depths ranging from 7 to 18 metres, averaging 8 metres. Water temperatures remain warm throughout the year, ranging between 22C and 29C. Divers and snorkelers should be aware of boat traffic and surf conditions in the area. The site supports a variety of reef fish and invertebrates typical of the subtropical Okinawa Islands habitat.

Imazuni is a reef and drop-off site located off Aka Island in the Kerama Islands. The topography features a shallow reef starting at 7 metres that transitions into a wall descending to 30 metres. Visibility is consistently 23 metres. Divers should expect a moderate current running along the drop-off, which requires careful management; it is recommended to stay near the reef and use the wall for shelter. The site is suitable for beginners and supports night diving. The habitat supports a variety of reef fish and invertebrates typical of the Okinawa Islands region.

Tatami-ishi on Ojima Island is a shallow reef site known for its distinctive hexagonal rock formations. Accessible via shore entry, the site is suitable for beginners and families, offering snorkeling opportunities within tide pools and crevices at high tide. Depths range from 1 to 5 metres, with an average of 3 metres. Visibility typically varies between 10 and 30 metres, and currents are generally mild. Water temperatures fluctuate between 22C and 29C throughout the year. Parking facilities are available for visitors at this location.

Eef Beach (Central) on Aka Island is a 2km stretch of white sand beach. The site features an inner lagoon with sandy bottom conditions, protected by an outer reef that keeps the water calm. Small coral heads are located closer to the reef edge. This site is suitable for beginners and offers shore access for snorkelling. Water temperatures range from 22C in February to 29C between July and September. Due to the protected nature of the lagoon, it provides a calm environment for those looking to snorkel in the Kerama Islands.

Tropical Fish House is a natural tide pool formed by volcanic rock on the northern coast of Aka Island. This shallow site is suitable for beginners and is accessed directly from the shore. Depths range from 1 to 3 metres, with an average depth of 2 metres. The site experiences mild currents and visibility typically fluctuates between 5 and 20 metres. Due to its shallow nature and protected rock formation, it provides a calm environment for snorkelling. Water temperatures vary throughout the year, ranging from 22C in February to 29C during the summer months.