I did not do the dive. However, dangers include that the blue hole is connected to the sea by a tunnel that appears shorter than it is – due to the clear water and the extreme dept of the cave, using the bottom as a reference becomes misleading (it appears to be 10 meters but it is actually 26 meters). More than one tank of air/gas is needed to safely complete the dive through the tunnel.
I heard that about 8 people a year die here at the blue hole or at “the divers cemetery”; a total of between 130-200 divers have died here thus far.
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