If you get the opportunity to swim among the fish and behold the beauty of the reefs, you should absolutely take it. These underwater ecosystems have been around for millions of years and are home to approximately 25% of all marine life. The vibrant colors and active wildlife will make a swim in the reefs an unforgettable experience.

In addition to providing a home to millions of fish and other marine species, coral reefs also play a vital role in tourism, coastal protection, and even healthcare. Scientists have discovered that over time, corals have developed chemical defenses to protect them from predators. These chemicals are being used in research related to cancer, Alzheimer's, and other medical ailments. How amazing is that? So where can you see fascinating coral reefs up close and personal? Take a look at 5 of the largest coral reefs in the world.

Florida Reefs, Florida Keys

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Florida has never had a problem attracting tourists. From Disney and Universal to white sandy beaches, the state is one of the most popular destinations for tourists in the United States. But for those who don't want to spend the hot summer days in line at one of the theme parks, Florida's reefs are must-see. Florida's coral reef is located just west of the Florida Keys. The reef extends roughly 360 miles long from Dry Tortugas National Park to the St. Lucie Inlet, and is approximately 10,000 years old.

The Florida reefs are the only coral reefs in the United States and are home to more than 45 species of stony corals and 35 species of octocorals. The reef also welcomes several different marine animals including grouper, stingrays, and parrotfish. The coral reefs are also great for the Florida economy — it's estimated that they generate approximately 36,000 jobs and bring in over $3 billion annually.

Mesoamerican Reef, Caribbean

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The Mesoamerican Reef is the largest barrier reef in the Western Hemisphere, running approximately 700 miles long. An enormous number of species call the reef home, with over 500 fish species residing within the reef as well as 60 types of hard corals. The Mesoamerican reef attracts divers from around the world to see the diverse marine life, including five different species of turtles and one of the largest collections of whale sharks.

Over the years, the people of the region have struggled to protect the reef against the effects of climate change. Rising waters and higher temperatures are leaving both the reef and the marine life vulnerable. The World Wildlife Fund works with locals and scientists to help protect the region by developing restoration and protection programs.

The Mesoamerican reef is centrally located between several popular tourist destinations including Cancun and the Riviera Maya. This makes it easily accessible and a great option for divers who are unable to make it to the Great Barrier Reef. But while it doesn't get the same attention as the Great Barrier Reef, many divers will tell you that it is just as beautiful and definitely worth the trip.

New Caledonian Barrier Reef, New Caledonia

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UNESCO considers the New Caledonian Barrier reef to be one of the most extensive and diverse coral reefs in the world. Over 1,700 species of fish, 48 species of shark, and 4 species of birds have been identified in the area. Along with the reefs in Fiji, these reefs are considered to be the most significant reefs in Oceania. The New Caledonian reefs are home to several species of threatened coral and marine animals. Over the years, the reefs have unfortunately suffered from natural and manmade threats. Luckily, the government has made moves to protect the area.

While visiting the reefs is still an option, you will have to be careful planning your trip to the New Caledonian Barrier Reef. The recent changes include tighter restrictions on tourism. This means that much of the reef is off-limits to the public, so you will need to make sure that you verify all of your plans before making your trip.

Red Sea Coral Reef, Red Sea

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The Red Sea Coral Reef is located off the coasts of Egypt, Saudi Arabia, and Israel. The area is home to some of the warmest sea waters in the world. While other reefs have suffered from coral bleaching due to rising water temperatures, the reefs in the Red Sea have shown remarkable resistance. Researchers think that there might be a remarkable heat-resistant algae protecting the reefs. The hope is that research from these reefs can help protect and renew struggling reefs around the world. The red sea reef is home to a diverse collection of coral, fish, and other marine species including the nudibranch, the feather star, and the yellow frogfish. Many areas of the reef have been untouched, providing some of the most beautiful dives in the world.

Great Barrier Reef, Australia

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The Great Barrier Reef is arguably the most well-known reef in the world, and one of the seven natural wonders of the world. Located off the coast of Australia, the Great Barrier Reef attracts dive enthusiasts from all around the world. The Great Barrier Reef is a UNESCO World Heritage site, which means it has "outstanding universal value." There's no doubt that the legendary Great Barrier Reef is a stunning display of nature's beauty.

The reef itself is made up of over 3,000 separate reef systems. As the largest barrier reef in the world, it is larger than the great wall of China and can be seen from space. Over 400 types of coral exist in the Great Barrier Reef, as well as over 1500 types of fish and more than 20 different reptiles.

You don't even have to know how to dive to enjoy the reef. The popular tourist destination attracts snorkelers, swimmers, and boaters as well. The warm water means that visitors can see the reef year-round, but National Geographic reports that the peak tourist season is between April and November, so plan your trip accordingly.