The Kerama Islands became Japan's thirty-first national park in March 2014, recognizing a coral ecosystem that hosts more than 250 species across twenty uninhabited islets and five inhabited atolls. Visibility in the Kerama Blue — the local term for the water's cobalt clarity — routinely exceeds thirty meters during the April-to-October season, conditions that draw marine biologists and recreational divers in equal measure. Green sea turtles nest on Tokashiki's western beaches between May and August, while hawksbill turtles patrol the drop-offs year-round. The archipelago lies thirty-five kilometers due west of Naha, a journey ferries complete in fifty minutes. The Keramashoto National Park designation protects 3,520 hectares of reef, lagoon, and coastal forest. Zamami Island's Ama Beach and Tokashiki's Aharen Beach anchor snorkeling circuits that traverse table coral gardens at depths of two to twelve meters. Beneath the surface, Acropora and Porites corals form terraces colonized by clownfish, parrotfish, and over sixty species of butterflyfish. The archipelago's geographic isolation — positioned between the East China Sea and the Philippine Plate — produces nutrient upwellings that sustain plankton blooms, which in turn support manta rays and seasonal whale shark sightings near Aka Island's southern shelf. Okinawa prefectural fisheries data from 2022 recorded a ninety-two percent recovery rate in hard coral cover following the 2016 bleaching event, a resilience marine ecologists attribute to the park's strict anchorage and fishing prohibitions. Day-tour operators now limit group sizes to fifteen per vessel under Environment Ministry guidelines issued in 2019. The regulations mandate briefings on fin technique and distance protocols around nesting turtles, measures that balance access with long-term reef health. A Kerama islands diving tour departs Naha's Tomari Port most mornings between seven-thirty and eight-thirty, timing designed to reach the dive sites before mid-morning currents strengthen. Full-day itineraries include two snorkel sessions, often pairing a shallow lagoon stop with a deeper reef wall, and a beach interval on Tokashiki or Zamami. The return crossing typically concludes by four in the afternoon, aligning with Naha's public transit schedules for onward connections.