Dragon Hole

Dragon Hole is the deepest underwater sinkhole (blue hole) in the world. It is located in the Paracel Islands at 16°31′30″N 111°46′04″E / 16.5249°N 111.7679°E / 16.5249; 111.7679Coordinates: 16°31′30″N 111°46′04″E / 16.5249°N 111.7679°E / 16.5249; 111.7679, near Discovery Reef. It is 300.89 metres (987.2 ft) deep.

The local fishermen call it the "eye" of the South China Sea, and believe it is where the Monkey King, in the novel "Journey to the West," found his golden cudgel.

The Dragon Hole is 300.89 m (987.2 ft) deep, which is almost a 100 m (300 ft) deeper than Dean's Blue Hole in the Bahamas. Blue holes are characteristically hundreds of feet deep and generate a distinctive blue color when seen from above.

There are a couple fresh water sinkholes on land that are deeper than Dragon Hole. These include the Mexico's Zacatón at 335 m (1,099 ft), the 392 m (1,286 ft) Pozzo del Merro in Italy. and the 404m Hranice abyss in the Czech republic.

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Wikipedia