NHK Great Nature - Explorers of the Deep Bahamas Blue Holes (2013)

Nearly a thousand caves dot the ocean floor near the Bahamas, southeast of the Florida peninsula. These “blue holes” are limestone caves that have formed over the course of 350,000 years. There's little oxygen in the water in these caves, making it incredibly transparent with an over 100-meter visibility. The caves reflect only the deepest blue spectrum of light. Inside are numerous stalactites. There are also calcareous crystals, some shaped like roses, that reflect light like quartz. In addition, the bones of ancient animals and humans have been found in these caves. Join us as we dive into this wondrous world.

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