The Great Blue Hole looks like a portal to another dimension—a dark, circular pit surrounded by lighter blues and greens to create a mesmerizing visual of depth from the surface. It's no surprise that it's a hit among divers, but the secrets of its depths are even more fascinating than its aesthetic allure.
Its Rise to Fame
Famous adventurer and filmmaker Jacques Cousteau was the first to really explore the depths of the Great Blue Hole in 1971. When he saw that its limestone cave formations featured stalactites and stalagmites, which only form above water via minerals dripping from cave ceilings, he realized that much of the Great Blue Hole had been on dry land being submerged over time as sea levels rose tens of thousands of years ago.
According to Belize.com, the aquatic wonder is 410 feet (125 meters) deep—taller than the world's tallest tree— and 984 feet (300 meters) across, which is more than three football fields placed end-to-end. It sits right in the middle of Lighthouse Reef, an eastern section of the Belize Barrier Reef, which is the one of the largest coral reef systems in the world, second only to the Great Barrier Reef in Australia. The intricate cave system, teeming with Caribbean reef sharks, is made even more awe-inspiring by the crystal-clear blue waters of the Caribbean Sea.
The Great Blue Hole is for more experienced divers only, as it requires a good amount of depth in order to really experience it. As Atlas Obscura writes, "It is said that the deeper one goes, the water becomes more clear and the formations, more complex." But what's really astonishing about the connectivity of the systems surrounding the Great Blue Hole is the fact that you can explore caves that were formed the same way above water. Either way, you can partake of the reef's jaw-dropping beauty.