Japan
Japan's busiest mainland dive coast, within easy reach of Tokyo, with volcanic reefs, soft corals, rich macro life in Suruga Bay and schooling hammerhead sharks at Mikomoto Island off the southern tip.
The Izu Peninsula in Shizuoka Prefecture lies between Sagami Bay and Suruga Bay, Japan's deepest bay, and is part of Fuji-Hakone-Izu National Park. The Japan National Tourism Organization lists more than 30 dive areas along its coasts, and most are served by local dive shops that run shore and boat dives as day or weekend trips from Tokyo. On the east coast, Izu Ocean Park near Ito is a long-established shore dive over old lava flows, and Futo and Kawana are known for spawning squid, eagle rays and turtles. On the west coast, Osezaki on Suruga Bay is famous for nudibranchs, occasional deep-water species and winter sunfish. Off the southern tip near Shimoda, Mikomoto Island is described as Japan's top hammerhead site, with schools from June to October in strong currents. The Kuroshio current warms the water to about 26 °C in late summer. Source: Wikipedia, JNTO, Dive Japan.