Beneath the waters off Hainan Island, unusual structures rest on the seafloor … shipwreck outlines, engine blocks, even statues. They resemble relics of an ancient civilization, but they're actually part of one of China's largest tropical marine conservation programs. On Wuzhizhou Island, experts are rebuilding coral ecosystems using artificial habitats, real-time underwater monitoring and a hands-on initiative that lets visitors help plant coral. We dive with conservationists, explore why China is working to revive these reefs, and even plant a coral "baby" ourselves. From reef restoration to rare marine sightings, this is how a tourist hotspot is becoming a model for ocean protection, one coral at a time.