An amazing phenomeno in Mexico was photographed by Anatoly Beloshchin: The underwater river ‘Cenote Angelita’ (in English ‘Little Angel’).
The forming of the river is caused by a three-foot thick layer of hydrogen sulfide that separates the 100-feet of freshwater at the top from the 100-feet of saltwater on the bottom, which leads to the idea that it is an actual river.
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