holes of Cay Sal Bank are most striking. These holes were most
likely formed during the ice age when the area was dry land. As
the earth collapsed forming a sink hole, a limestone substrate
become exposed. Millions of years later as water began to cover
the bank, these narrow ridges of limestone became a perfect base
for corals and sponges to attach.
Today, divers can enjoy the ancient
coral that covers the rims of the blue holes that begin in about
20 -30 feet of water. Colorful tropical fish dart in and out of
the coral. Octopus and huge basket stars come out after dark.
And a plethora reef sharks call the blue holes home as well make
blue hole dives an exciting experience.
The smallest blue hole at Cay Sal Bank
is a hundred yards wide, while the largest is a quarter of a
mile in diameter. The depth sounder on the boat reads to
approximately 400 feet at the holes' centers. The clear waters
can have visibility exceeding 100 feet, revealing galleries of
stalagmite and stalactite that are more proof that these holes
were once caves on dry land.