Local Ainan boat-dive support and fish-rich diving context.
Boat-access coral and cave dive off Ainan, Japan.
Boat-access coral and cave dive off Ainan, Japan.
Koyoko Island is a boat-accessed dive site in Ainan with coral-covered terrain, dense fish life, and a cave section reached after the safety stop. The shallow entry makes it approachable for newer divers, but the site is tide-sensitive and can tighten up when current builds. Plan the dive with local boat support and a low-tide window if possible.
Conservative baseline from public research. No community dives logged yet.
Depth range, seasonality, and planning context.
Reported Depth
5m - 18m
Depth Note
Boat entry begins around 5 m; the site profile reaches about 18 m.
Best Season
Winter is the calmer, clearer window; low tide helps in other seasons.
Typical Conditions
Shallow boat entry with a generally manageable profile; low tide is the safer window because current can strengthen.
Hazards, restrictions, and access requirements.
Key Hazards
Safety Notes
Keep an eye on tide timing, and treat the cave section with standard overhead caution after the safety stop.
Community notes to help plan your visit.
Scuba Diving
Suitable for beginners with a calm shallow start; caves can be explored after the safety stop.
Species commonly reported at this site, with direct links into their wildlife guides.
Community dive logs and visit reports for this site.
Average conditions based on logged dives & visits.
Planning answers for access, conditions, timing, and site logistics.
Last Updated
Research Sources
Local Ainan boat-dive support and fish-rich diving context.
Official Ainan marine-park context, coral forest, and boat access information for the surrounding area.
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