Located around the Yongle atoll of the Xisha Islands, one of the world's biggest ocean blue holes was named as "Sansha Yongle Blue Hole" by China's Sansha municipal government.
The blue hole is a vertical cave of 300.89 meters' depth, with its entrance diameter reaching 130 meters and its bottom's diameter stretching 36 meters. So far, no connections between the hole and the outside sea waters have been found and the water inside the cave does not flow.
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One of the world's biggest ocean blue holes has been named "Sansha Yongle". (Photo / chinanews.com) |
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The ocean blue hole is located in the waters of China's Sansha city. (Photo / chinanews.com) |