​​UNESCO has proposed the entire reef system on the south coast of Cuba as a "World Heritage Site" 

It is a cluster of different ecologically associated marine-coastal areas located in southern Cuba and mainly linked to two small-island archipelagos to the South of the island of Cuba that are known as Canarreos and Jardines de la Reina. The proposal stretches from Guanahacabibes Peninsula in westernmost Cuba to Jardines de la Reina in southern Cuba.

This 800-km-long system includes 9 protected areas comprising the main marine areas in Cuba and the most important ones in the insular Caribbean due to their extension, natural values and conservation status. The proposed site is a cluster of different ecologically associated marine-coastal areas located in southern Cuba and mainly linked to two small-island archipelagos to the South of the island of Cuba that are known as Canarreos and Jardines de la Reina.

According to their geographical location from West to East, these areas are:

1. Jardines de la Reina National Park
Being the largest, most pristine and natural Cuban marine ecosystem, it is formed of the archipelago of the same name and has the largest populations of Hawksbill (Eretmochelys imbricata) and Loggerhead (Careta Careta) in the insular Caribbean, the other marine chelonian populations standing out too.
As to fish, this Park harbors the largest populations in Cuba - possibly in the Caribbean. The coral reef conservation status is very good.
The Park stretches along 2,170 km2.

2. Banco de Jagua Fauna Refuge
It is a completely marine area made up in the upper part of an underwater elevation off the Cuban insular shelf that is a distinctive trait of the Cuban underwater world. It houses extensive coral systems.

3. Este de Cayo Largo Ecological Reserve
Located near the eastern border of the Canarreos Archipelago, this reserve encompasses the largest calcareous and oolithic sand key in the Caribbean. I also includes reefs and seagrass beds.

4. Cayos Avalos Cantiles Rosario National Park
It is a complex of keys with different origins such as Cayo Cantiles that houses almost ten local endemics; the Park is a unique example of a small-islands natural evolutionary laboratory.  Cayo Rosario shelters the largest population of Iguana (Ciclura nubila nubila) while Cayo Avalo houses the largest underwater archeological flotsam site in Cuba. This Park includes a whole range of seagrass beds and coral reefs typical to these ecosystems.

5. Punta del Este Ecological Reserve
Punta del Este Ecological Reserve: Located in the southeastern border in the second largest island (Isle of Youth) of the Cuban archipelago, it comprise the main rupestrian-paintcontaining site in Cuba, and one of the most important ones in the Caribbean. It includes typically terrestrial ecosystems as well as submarine ones. It is a very important area for reef fish and spiny lobster raising in Cuba.

6. Punta Frances National Park
Being the best known Cuban underwater site and possibly one of the most developed ones concerning deep front coral reef formations, it has over ten well-preserved underwater caves.

7. San Felipe - Los Indios National Park
Formed of the westernmost Canarreos Archipelago, it includes the clusters of keys with the same name. Here we can find a relic population of a Cuban endemic mammal, the San Felipe Hutia (Capromys sanfelipensis) as well as two other local endemic fauna species. It is very important to the spiny lobster and other commercially important species due to the partial retention produced by a gyring current to the south of the area. This Park harbors well-preserved underwater ecosystems.

8. Guanahacabibes National Park
Guanahacabibes National Park: Situated in westernmost Cuba, it is the core area of the Biosphere Reserve of the same name. There are very well-preserved coral ecosystems. This area is one of the main spawning zones for porgies and groupers, thus constituting one of the sources that contribute most with these species to the Canarreos Archipelago and the Batabano Gulf, given the prevailing system of currents to the East. 

9. Banco de Knoll Natural Outstanding Element
It is a deep underwater bank formed of an odd submarine elevation off the insular shelf. Interesting megalithic structures located several hundreds of meters deep were recently discovered here and are currently under study. Most of these areas relate to the two most extensive Cuban archipelagos after that situated to the North (Sabana-Camaguey) and include over 1,200 keys and islets. Its ecosystems are very rich and well preserved while the status of the populations existing there is very good. Some of the threatened species are the 4 chelonian species living in Cuba, which are most splendid in Jardines de la Reina; the populations of manatees and crocodiles, which are superlative in the Cienaga de Zapata -- including the only population of the Cuban crocodile (Cocodrilus rhombifer). The fringing-barrier coral reef system along the insular border is extensive and almost continuous, forming the longest barrier of this type in the insular Caribbean. A great deal of this system is located 30-100 km off the Island of Cuba, though some areas are adjacent to the coast of the Island of Cuba. In all cases, the system of keys and the karstic lithology (contributions of freshwater, sediments and nutrients) account for highly related marine and terrestrial ecosystems. The aforementioned condition differs in only two completely marine areas constituting isolated banks off the insular shelf and being true underwater "Islands" isolated in midocean. The reef system has generally undergone low levels of disturbance, the highest ones relating to natural causes such as hurricanes and global or regional effects such as mortality of black long-spined sea urchins, coral diseases, bleaching, etc.

Source: UNESCO

​More on Gardens of the Queen:

The Queen's Gardens, are located 60 Miles off the southern coast of Cuba, this archipelago comprises a chain of 250 virgin coral and mangrove islands extending along 75 miles of turquoise waters. The Jardines de la Reina was declared Marine Park in 1996, and together with the Cuban Sciences and Environment Ministry, this area has been preserved for future generations, as a complex network of untouched marine ecosystems that have been regarded by many knowledgeable scientists and organizations as a reference of what is the original status of a coral reef as it was found by Cristopher Colombus in the times of the discovery.

The underwater paradise is all that comes into your mind when you first enter the water, imagine the vertical walls covered with brightly hued sponges, huge Pilar Corals ,black corals extending the branches in the contrasting blue water, many species of gorgonians, fragile laminar corals , showing its beautiful shapes through crevices, canyons and caves .The mangroves providing an incredible nursery area for young fish populations, filtering the water that goes to the reef together with the seagrass beds and in return receiving protection from the open ocean wave energy, all interconnected in a very fragile net that here keeps its variety, richness and splendor.

The biggest populations of adult fish in the Caribbean, Sharks, Snappers and Groupers, Jewfish up to 400 Pounds are an everyday experience. Sharks are one of the main attractions and you can see them everywhere. You can easily dive with 6 different species: Silkies, Reef, Lemon, Black tip, King Hammerhead and nurse sharks. From July to November you have chances to swim with Whale Sharks. . Gardens of the Queen are certainly one of the last virgin reefs known by man. Dive and snorkel sites are well protected from the winds and sea currents. Visibility is more than 40 meters. There is a wide variety of fish and corals.  You can appreciate all this also snorkeling!!!!!

 The Gardens of the Queen Marine Park is a wonderful place, both in and out of the water. This marine park is probably the most important group of islands in the Caribbean, integrated for one million-acre wetlands. In addition, this marine park acts as a critical refuge for North American birds migrating along the route through Florida and the Gulf of Mexico to South America. This wildlife sanctuary hosts more than 68 species of migratory birds.