West of Misool, located not far from the island’s only harbor, a mysterious Blue Hole known only to locals remains hidden just a few feet deep. As its name suggests, this formation is characterized by a dark blue colored hole tending more towards black. The entrance to the blue hole, being at a depth of twelve meters, makes it difficult to see for anyone out of the water. Blues holes, or submerged sinkholes, are karstic formations resulting from the erosion of carbo- nated geological formations. This blue hole was previously in the open air, certainly during the Pleistocene geological era. The combined efforts of the elements (rain, wind, river, etc.) have created this hole over the millennia. Diving into a blue hole is like going back in time. From its entrance at twelve meters up to forty-five meters deep, the gallery is vertical. With a diameter of around ten meters, the atmosphere is extraordinary. Here, little or no wildlife to contemplate, it is the geological and mineral aspect that picks our imagination. From forty-five meters deep, the gallery becomes oblique to the bottom of the submerged tunnel sixty-four meters deep. There, the light is almost absent, but that does not prevent some living organisms from thriving on the limestone walls.

From this point, the light is almost absent, but that does not prevent some living organisms from thriving as best they can on the limestone walls.