Belize's Blue Hole Mystery

The Great Blue Hole in Belize is a breathtaking natural wonder located in the shallow waters of the Lighthouse Reef Atoll, about 43 miles from the mainland. This giant marine sinkhole, made famous by Jacques Cousteau, is a popular diving destination, known for its unique circular shape and rich blue colour. With a depth of over 400 feet and a circumference of almost 1,000 feet, it is believed to be the largest sea hole in the world. The Great Blue Hole was formed thousands of years ago when rising sea levels flooded a network of caves, leaving behind impressive geological formations such as stalactites and stalagmites. Today, divers can explore these ancient caverns and encounter a variety of marine life, including Caribbean Reef Sharks and the elusive Hammerhead Shark.

The Great Blue Hole

The Blue Hole offers a unique diving experience with its vertical plunge, passing marine life, and ancient stalactites and stalagmites in the depths. The entire area surrounding the hole is ideal for spotting tropical fish, shrimp, and other Caribbean wildlife. However, only qualified divers with the necessary certifications are allowed to dive here due to the technical nature of the dive.

For those who prefer not to dive, the Great Blue Hole can also be experienced through snorkelling, aerial tours, or boat tours around the hole and nearby reefs. The surrounding area boasts pristine beaches and small islands, offering a range of attractions for visitors to enjoy.

A UNESCO World Heritage Site

The Great Blue Hole, a giant marine sinkhole off the coast of Belize, is a UNESCO World Heritage Site. It is located near the centre of Lighthouse Reef, a small atoll 70km from the mainland and Belize City. The Great Blue Hole is circular in shape, 318m across and 124m deep, with a surface area of 70,650 square metres.

The Great Blue Hole is part of the Belize Barrier Reef Reserve System, which was designated as a UNESCO World Heritage Site in 1996. The Belize Barrier Reef Reserve System is the largest reef complex in the Atlantic-Caribbean region and the second-largest reef system in the world. It is comprised of seven protected areas: Bacalar Chico National Park and Marine Reserve, Blue Hole Natural Monument, Half Moon Caye Natural Monument, South Water Caye Marine Reserve, Glover's Reef Marine Reserve, Laughing Bird Caye National Park, and Sapodilla Cayes Marine Reserve. These seven protected areas make up 12% of the entire reef complex.

The Great Blue Hole is believed to be the world's largest feature of its kind. It was formed during the last glacial period, sometime between 25,000 to 100,000 years ago (with some experts suggesting it could be as old as 150,000 years), and was later flooded by rising ocean levels. The sinkhole is characterised by its deep blue hue, encircled by the lighter shades of Belize's Lighthouse Reef. This contrast makes it visible even from space.

The Great Blue Hole is one of the most famous and popular dive sites in the world, attracting recreational scuba divers who want to explore its depths. It was made famous by Jacques Cousteau, who visited in the 1970s and declared it one of the best diving spots in the world. The site offers divers the opportunity to see millennia-old stalactites and stalagmites, as well as a variety of marine life, including tropical fish, spectacular coral formations, nurse sharks, giant groupers, and several types of reef sharks.

Diving in the Great Blue Hole is not for beginners and is considered an advanced dive. Divers need at least an Open Water or Advanced Open Water diving certification and must be able to descend to depths of 130-135 feet. The dive typically involves a quick descent, a brief stay at that depth, and a cautious ascent. When diving in a group of ten or more, it is recommended to have at least three dive masters present.

A popular diving site

The Great Blue Hole is a giant marine sinkhole off the coast of Belize. It is one of the most famous dive sites in the world, attracting divers from across the globe who want to explore its depths. It is located near the centre of Lighthouse Reef, a small atoll 70km (43 miles) from the mainland and Belize City. The Great Blue Hole is almost perfectly circular in shape, measuring 300 metres (984 feet) across and 124 metres (407 feet) deep.

The Great Blue Hole is believed to be the largest natural formation of its kind in the world. It is part of the Belize Barrier Reef Reserve System, a UNESCO World Heritage Site. The sinkhole is thought to have formed during the last glacial period, between 25,000 and 100,000 years ago, and was later flooded by rising ocean levels.

The site was made famous by Jacques Cousteau, who visited in the 1970s and declared it one of the top five scuba diving sites in the world. Cousteau and his crew explored the depths of the Blue Hole, confirming that it had been created thousands of years ago when rising tides flooded a network of caves.

The Great Blue Hole is a popular destination for recreational scuba divers making day trips from the coastal tourist communities in Belize. It is not a dive for beginners, however, and only those who are fully qualified and experienced can dive here. Divers need at least an Open Water or Advanced Open Water diving certification. Before diving the Blue Hole, divers will typically practice their skills with a divemaster who will make the final call on whether their skills are up to the challenge.

The Blue Hole is home to a variety of marine life, including nurse sharks, reef sharks, black-tip sharks, and even hammerhead sharks. Divers can also explore the thousands of stalactites and stalagmites that were formed when the Blue Hole was an above-ground series of caverns.

The best months to dive the Great Blue Hole are April, May, and June, when you'll have peak visibility, fewer crowds, and the potential to see whale sharks.

Jacques Cousteau's endorsement

The Blue Hole in Belize is a breathtaking natural wonder, a giant marine sinkhole off the coast of Belize. Located in the shallow waters of the Lighthouse Reef Atoll, it is a circular hole almost 1,000 feet across and over 400 feet deep. This collapsed cave system was likely formed above ground around 10,000-15,000 years ago at the end of the last Ice Age.

The Blue Hole is one of the most iconic dive spots in Belize and was made famous by Jacques Cousteau, the legendary French documentarian, naval officer, conservationist, filmmaker, innovator, scientist, photographer, author, and underwater explorer. In 1971 or 1972, Cousteau brought his renowned research ship, the Calypso, to investigate the depths of this sinkhole. He later described the Blue Hole as one of his top favourite dive sites in the world, declaring it one of the top five scuba diving sites.

Cousteau's expedition confirmed the hole's origin as typical karst limestone formations, formed before rises in sea level in at least four stages, leaving ledges at various depths. They retrieved stalactites from submerged caves, confirming their previous formation above sea level. Some of these stalactites were also off-vertical, indicating that there had been some past geological shift and tilting of the underlying plateau. Cousteau's team also found that the Blue Hole was surrounded by reefs, caves, and several species of fish, including bull sharks, hammerheads, and midnight parrotfish.

Cousteau's visit brought worldwide attention to the Blue Hole, and it is now a bucket list dive site for scuba divers. The Blue Hole is part of the Belize Barrier Reef Reserve System, a UNESCO World Heritage Site, and is ranked as one of the top ten dive sites in the world.

In addition to his exploration of the Blue Hole, Cousteau is known for his pioneering work in scuba gear and underwater base camps. He co-created the Aqua-Lung, a twin-hose underwater breathing apparatus, and created the first underwater habitat for humans, Conshelf I, followed by Conshelf II and III. These habitats could house working oceanauts for extended periods. Cousteau was also a prominent conservationist, helping to restrict commercial whaling and stop the underwater dumping of nuclear waste. His legacy continues through the Cousteau Society, which he founded in 1973, with over 50,000 members worldwide, dedicated to exploring and protecting ecosystems around the world.

How to visit

The Great Blue Hole in Belize is a once-in-a-lifetime destination and one of the top diving sites in the world. Here is how you can visit this breathtaking natural wonder.

Location

The Great Blue Hole is a giant marine sinkhole located near the centre of Lighthouse Reef Atoll, a small atoll off the coast of Belize. It is about 43 miles (70km) from the mainland and Belize City.

Getting There

Most visitors to the Great Blue Hole will arrive by boat or helicopter from one of Belize's many barrier islands. The journey by boat can take between three and four hours, depending on whether you are travelling from the north or the south. If you are looking for a budget-friendly option, you can arrange a shared tour with a local tour operator such as Amigos Del Mar. For a more intimate experience, you can charter a boat exclusively for your group or book a multi-night catamaran adventure.

By Air

For the ultimate in luxury, charter a catamaran and enjoy your own floating hotel. With this option, you will have a local guide as a captain and a chef as a first mate, with the nightly rate including meals, drinks, snorkel equipment and more. You will also be able to visit several of the remote tropical islands that are part of the atoll.

If you are not interested in diving, you can opt for a helicopter tour, which will allow you to see the Blue Hole from above and take amazing pictures. Fly-over tours are fast and provide gorgeous visuals of the entire site. Tropic Air offers fly-overs twice a week from Ambergris Caye.

Diving

The Great Blue Hole is a dive site for experienced divers only. To be qualified to dive here, you need at least an Open Water or Advanced Open Water diving certification. Divers will typically practice their skills with a divemaster who will make the final call on whether their skills are up to the challenge. There are several dive shops on San Pedro in Ambergris Caye, including Belize Pro Dive Centre, Ambergris Divers, Belize Diving Adventures and Amigos Del Mar. You can also depart from Caye Caulker, which has dive shops such as Scuba Sensation and Frenchie's Diving.

The best months to dive the Great Blue Hole are April, May and June, when you will have peak visibility, fewer crowds and the potential to see whale sharks.

Frequently asked questions