Sea cliffs of black volcanic rock and red tuff, coral communities on the shallow flanks with visibility that reaches 25 metres…Sea cliffs of black volcanic rock and red tuff, coral communities on the shallow flanks with visibility that reaches 25 metres on the best days, and a Gothic Catholic church built by French missionaries in 1853 out of coral blocks quarried from the island's own reef. Weizhou is China's largest and youngest volcanic island, and its coral has taken heavy pressure from fishing and tourism, which is why there is now a national marine park around it. Bryde's whales began appearing in numbers off the island in the 2010s, the only known coastal feeding ground for them in Chinese waters. Anchorage: Weizhou harbour and the sheltered bays; the island sits in the Gulf of Tonkin between China and Vietnam. Hazards: Typhoon season Jul-Sep, and visibility varies enormously with the season. Altro