Hong Kong's Hidden Supervolcano: Ancient Power & Splitdyboat Geopark Adventures
Hong Kong's High Island supervolcano, discovered in 2012, erupted around 140 million years ago during the Cretaceous period, forming the core of the Sai Kung Volcanic Rock Region in the UNESCO Global Geopark. This ancient caldera, spanning about 11 miles in diameter, unleashed over 1,300 cubic kilometers of ash—enough to bury modern Hong Kong under 1.3 km thick or cover 1.3 million sq km at 1m depth—ranking as a VEI 8 eruption, 10,000 times stronger than Iceland's recent events and surpassing Yellowstone's latest in volume. Its remnants created rare hexagonal rhyolite columns, sea arches, and dramatic cliffs visible today, shaped by massive subduction zone activity off ancient China's coast.
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Splitdyboat Geopark Tours
Explore these supervolcano rock formations via Splitdyboat's speedboat adventures from Sai Kung, with pro tour guides explaining the geology.
Ninepin Group Island Hopping Tour (HK$580/person): Hop 8 attractions like North Ninepin's Moon Cliff hexagonal columns, Big Cannon Rock, Silver Bottle Sanctuary, and South Ninepin's Three Dragon Mouth tunnel cave—Y-shaped cave. Speedboat transfers showcase the world's largest hexagonal volcanic columns. What makes it even better? Option to Board the Speedboat from Town Centre - Tseung Kwan O.
Geopark Four Sea Arches Volcano Sightseeing Tour (2-Hour Speedboat Edition) (HK$480/person): Cruise to the SuperVolcano Relic, the shore of hundred thousand columns in High Island, also exploring the four largest East Sea arches—Wang Chau Kok Cave (Little Taiwan), Guandao Cave (Lam Wan Kok), Bluff Island Cave, Tiu Chung Cave (Bell Cave, 30m tall, widest arch). Bonus: Speedboat through arches if waves allow.
Geopark Four Sea Arches Volcano Sightseeing Tour (4-Hour Yacht Edition): Comfort guided yacht cruise explores 11 UNESCO Geopark attractions including Jin Island's dramatic Bell Cave, Sharp Island landings (Pineapple Bun Rock, Angel Road), plus Hung Shing Temple fisherman village walk—perfect for families/seniors seeking stable, spacious comfort with sunset views, guided geology insights, and pro photography assistance.
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These tours reveal Hong Kong's explosive past up close—
book via Splitdyboat Official Website for geopark thrills!
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