Blue Hole (cavern/cave) Diving Grand Bahama Island
Location: 
Inland (Lucayan National Park and surrounding area.
The caves and Caverns are a hiddin part of Grand bahama, a secret realm that only a few visitors will ever know about or take the time to understand. What you cannot see beneath the surface is an immense underwater cavern, the gateway to a vast, flooded, labyrinth of caverns, caves and submerged tunnels that honeycomb the entire island of Grand Bahama and the surrounding sea bed.
For the most part, the inland caves are not exactly teaming with life but there are creatures living in the caves other than the migrating Grey Snappers. The full time residents include a type of blind cave fish and a relatively new species of animal found lurking in dark passages. Fortunately, the creature, Speleonectes Lucayensis, is not a threat to cave divers. It's only an inch or so in length and looks a bit like a swimming centipede.
The caves in the Bahamas were formed during the last ice age. With much of the earth's water held in the form of glacial ice, the sea level fell hunderds of feet, leving most of the Bahama banks, which are now covered in water, high and dry. Rain falling on the most porous limestone, slowly filtered down to sea level forming a lens where it contacted the denser salt water of the ocean permeating the spongy lime stone. The water at the interface, was acidic enough to disolve away the limestone and form the caves. Then, as more ice formed and the sea level dropped even further, the caves became dry and rainwater dripping through the ceiling, over thousands of years, created the incredible crystal forests of stalagmites which now decorate the caves. Finally, when the ice melted and the sea level rose, the caves were reclamed by the sea.
The surface water you see in these caves is fresh and pure. It's rainwater that seeps through the porous limestone just as it did when the caves were created, forming a gient lens that floats on the under layer of sea water. When you dive in the caves, at a depth of about 25 to 30 feet, you can see the fresh / alt water interface, or "halocline," as a distinct line seperating the liquids, and if you watch a diver passing through the halocline, their image is momentarily blurred and distorted by the mixing of the fresh and salt water.
Cavern tours:
Cavern tours are available to any open water certified diver, and offer a chance to explore underwater forests of stalagmites and stalactites, pass through the weird transition zone between fresh and salt water(or halocline), and see ancient fossilized coral reefs, all in the absolute quiet and calm of the area of the cave where ambient light from the entrance is always visible. Our cavern guides are all cave certified and equipped, as well as open water divemasters or higher, and we restrict our groups to a maximum of 4 divers per guide. Grand Bahama Island offers 3 cavern zones large enough for an excellent cavern diving experience, they are:
Ben's Cavern
Located in the Lucayan National Park, Ben's is the easiest of the cavern dives, yet offers all of the aspects which makes cavern diving special, including speleothems, halocline, fossilized coral reef and calcite crystals, all housed within a large and beautiful ambient light zone. Park rules which allow only one group of divers every second day guarantee perfect conditions, but necessitate early reservations. An additional $10 entrance fee is charged by the National Trust.
Mermaid's Lair
For the diver who relishes leaving the beaten path, Mermaid's is the place for you. The entrance pool looks like a puddle hidden among the Bahamian forest, upon entering; you'll find yourself in a huge room offering some of the best cave formations to be seen within any cavern zone.
Owl Hole
The forty foot descent to the water by ladder leaves this cavern for the dedicated cavern explorer only. The reward awaits underwater, with the largest of the island's ambient light zones, pristine halocline, and stunning views back towards the entrance.
Cave Diving Tours:
For certified cave divers only! Grand Bahama Island offers nearly 10 miles of explored underwater cave.
