Blue holes are a natural phenomenon that never fails to awe and inspire divers around the world. These submarine caves and limestone sinkholes have received their name due to their deep blue color, which contrasts against the lighter blue shallow waters that surround them. There are a multitude of these underwater holes around the globe, but only a handful are frequented by divers.
Great Blue Hole – Belize
As the prized discovery of Jacques Cousteau, the Great Blue Hole is the most famous submarine cave in the world, and is the dream of every diver. At 305 meters across and 123 meters deep, this famed dive site in the Lighthouse Reef Atoll off the coast of Belize is a mecca for divers wanting to experience giant underwater stalagmites and stalactites. Around 30 meters down, the hole’s limestone formations become increasingly intricate. For divers qualified to dive below 40 meters, the site is a stunning marvel of nature’s beauty.
Dahab Blue Hole – Egypt
A couple of decades ago, Dahab was nothing more than a small Bedouin fishing village on Egypt’s Sinai coast. Today, it’s known the world over for its terrific windsurfing conditions and perhaps the best shore diving in the world. Known as one of the most dangerous dive sites in the world, Dahab’s hole can be accessed from shore, making it dangerously tempting. It has a depth of 130 meters, but a tunnel is located only 52 meters down, tempting divers to go beyond the recreational dive limit to experience the Egyptian hole’s amazing scenery. Unfortunately, some divers miss the tunnel and go too low, never to be seen again.
Dean’s Blue Hole – Bahamas
Dean’s Blue Hole in the Bahamas is one of the deepest holes in the world. Unlike the previous holes mentioned, it widens only 20 meters down into a 100 meter underwater cavern, making it a popular Caribbean dive spot. In fact, the site hosted the Vertical Blue 2008 free diving competition, in which five world records and 25 national records were broken. A year later, New Zealand free diver William Trubridge obliterated the free diving world record when he reached a depth of 84 meters without even using fins.