Diving and Snorkeling the Blue Holes of the Out Islands
Early inhabitants of The Bahamas both feared and revered the country’s many mysterious blue holes; today’s visiting divers and snorkelers will find these natural wonders fascinating places to explore.
The Bahamas was literally built by the sea, with corals and other industrious underwater creatures laying down a vast shelf of limestone that includes all the Out Islands. During the Pleistocene Epoch, though, when up to 30% of earth was covered in ice, so much water was frozen that sea levels dropped 300 feet, leaving the Bahama banks high and dry. With the Bahamas stony plateaus soaring above the waves, rain formed ponds, puddles and streams of groundwater (always slightly acidic) that ate its way through the limestone, ultimately forming one of the world’s most extensive cave systems. Once the glaciers receded and the sea level rose, these caves and caverns flooded.
A Diver’s Geological Wonder
Standing on one of the Out Islands, you can imagine you’re atop a gigantic natural sponge that’s soaking in a bath of warm water. A few bits barely stick up out of the water – those are the islands – while the rest of it is below sea level and riddled with flooded passageways (only 10% which have been explored). Classic blue holes – round unblinking eyes that you see staring at you as you fly over the Out Islands’ shallow banks or forests – are formed when the ceilings of large caves collapse, exposing vertical shafts to the sky. The name “blue hole” comes from the indigo color of the water in the center of the opening as compared to either the aquamarine of the surrounding shallows or, if it’s an inland blue hole, the gray of the surrounding ironshore or green of the trees. Dean’s Blue Hole, visited by divers on Long Island is a beautiful example of a classic blue hole with the added attraction of mystery – it’s the deepest blue hole in the world, twice as deep as any Pleistocene era cave should be.
Blue Holes occur all over The Bahamas, but Andros is the holy (pun intended) grail for divers looking to explore these caves.
Andros Island Blue Holes
Blue Holes occur all over the Bahamas, but Andros is the holy (pun intended) grail for divers looking to explore these caves. The expert guides at Small Hope Bay are the cave and cavern kings when it comes to escorting divers into the underworld. Some of their sites are suitable for any divers, while others are expeditions for advanced divers only, where a guide plus one or two guests delves deep into the dark recesses under the island, sometimes squeezing though small openings that then open up into awesome, cathedral-size caverns. Divers can see for themselves the proof that these caves were created when the sea level was much lower as they’ll swim alongside dramatic stalagmites and dripstones, which can only form in air.
On South Andros, even snorkelers can explore blue holes, swimming above the entrances to caves where colorful reef fish gather to feed in the currents that move through the cave as it “breathes” with the tide (the Bahamas’ early inhabitants, seeing the swirling currents above blue holes thought that sea monsters lived inside, waiting to suck down boats and swimmers). A completely different experience is snorkeling “The Crack” at Tiamo. Here, you swim into a deep water-filled fault line, feeling like you’re flying through the Grand Canyon only better: because it’s filled with fish.