Osezaki

Osezaki is an advanced dive site on the Izu Peninsula in Shizuoka Prefecture, widely regarded as one of Japan's top diving destinations. The site features a dramatic volcanic coastline where the mountainous terrain continues underwater as steep walls and boulder fields descending to 40 meters and beyond. The cold Oyashio and warm Kuroshio currents converge here, creating conditions that support an exceptional diversity of marine life. In winter, vast schools of sardines form mesmerizing bait balls, attracting yellowtail amberjack and other predators in spectacular feeding displays. Nudibranch diversity is extraordinary year-round, with over 150 species recorded. The deeper sections host gorgonian fans, soft corals, and rare deep-water species. With views of Mount Fuji on clear days, Osezaki offers a quintessentially Japanese diving experience — world-class marine life framed by one of the country's most iconic landscapes.