Where is the Dragon Nora - the deepest blue hole on the planet

Large karst funnels, from one species of which are breathtaking, are found in different parts of the oceans. The most famous of them is the Big Blue Hole off the coast of Belize, where thousands of divers from all over the world come annually. Despite its wide popularity, this funnel, to the bottom of which is exactly 120 meters, is far from the deepest. And the record holder among such natural phenomena is the blue hole of the Dragon Nora, located in the South China Sea.

The Dragon Nora is located in the middle of reefs, at a distance of 25 kilometers from the Paracel Islands. It was examined in detail by Chinese experts in 2016. Scientists used the latest high-precision equipment, which made it possible to measure the depth of the object, analyze the structure of the walls of the funnel, and also determine the physicochemical parameters of water at different depths. It turned out that it is much deeper than all the other blue holes on our planet. Its depth, according to preliminary estimates, is 300.9 meters, while the previous record holder, Dean's karst funnel, can boast only an indicator of 202 meters. The diameter of the Dragon Burrow at the surface is 130 meters.

As in other ocean funnels, in the Dragon Burrow, the oxygen content in the water column decreases with increasing depth. Starting from 40 meters there is a sharp decrease in oxygen levels, and deeper than 100 meters it is already absent. For this reason, fauna representatives are found only in the surface water layer, and in all 20 species of living organisms, including fish and marine microorganisms, were recorded. The Chinese scientists who examined the funnel did not find holes in its underwater walls, so they suggested that it did not communicate with the waters of the sea in its deepwater part.

Despite the fact that experts only recently studied the Dragon Burrow, sailors knew about its existence several centuries ago. Another local name for the karst funnel is the Eye of the South China Sea, under which it appears in several legends and Chinese literary works. Due to the colossal depth, the color of the water above the Dragon Burrow is much darker than that of the surrounding sea, so it is clearly visible from the plane. Of course, such an outstanding water body is of interest not only to scientists, but also to many divers who also want to reveal the secrets of the impressive Dragon Nora. But, alas, divers will not get here soon.

The fact is that the Paracel Islands, not far from which the Dragon Nora is located, are the subject of an international dispute. In addition to China, which declared them to be its territory more than 40 years ago, neighboring countries are claiming them. The warships of Vietnam and China regularly run here, and the area of these tropical islands cannot be called a paradise. Due to the uncertain status, the islands remain uninhabited. Unfortunately, due to political instability and the lack of infrastructure for tourist areas, the Dragon Nora will not soon become a popular place for diving.