Bikuni Treasure Island in Japan offers a combination of reef and cave topography suitable for beginner divers. The site reaches depths between 5 and 14 metres, with visibility ranging from 10 to 20 metres. Access is by boat only, and divers should expect mild currents. The cave structure presents an overhead environment, requiring careful buoyancy control and awareness of the roof. Divers can explore the reef and cave walls, which support a variety of temperate marine life typical of the region. Due to water temperatures ranging from 6C to 22C, a thick 4-5mm wetsuit is strongly recommended for this year-round cold water site.

Nagashima Kaiba 1 is a reef system located in the Sea of Japan, offering depths between 6 and 18 metres with an average of 10 metres. Visibility at this site ranges from 10 to 25 metres. Divers must use a boat for all entries to avoid surf and shore break. The site is suited for intermediate divers due to moderate currents that persist across the reef. Water temperatures fluctuate significantly throughout the year, ranging from 6C in the winter to 22C in September, requiring appropriate thermal protection for the season. Monitor depth carefully while navigating the reef to manage the current.

Shark Fin is a shore-entry site in Japan featuring a combination of reef and cave topography. The site ranges from 5 to 23 metres in depth, with an average of 10 metres. Divers encounter mild currents and visibility between 5 and 25 metres. The cave structure presents an overhead environment, requiring careful buoyancy control and positioning. The habitat supports various temperate marine life, including reef fish and invertebrates. Given the water temperatures, which range from 6 to 21 degrees Celsius, drysuits are recommended. On-site facilities include parking and toilets, making this a convenient location for beginners to explore the reef and cave features.