When speaking about coral reefs, we usually imagine an underwater "kingdom" with colourful fish and sea stars scurrying around bright branchy corals. But there are also coral reefs existing above the sea surface. They are known as raised (or uplifted) coral atolls: they were lifted high above sea level by tectonic forces, then the wind brought soils that enabled species of flora and fauna to develop here.

The largest formation of this kind reaches 8 meters in height: it is Aldabra atoll in the Indian Ocean. It is a part of the Outer Islands of Seychelles located in the south-westernmost point of the archipelago, but it doesn't look anything like other islands of Seychelles. The overall area of Aldabra is 155 sq km (34 km in length and 13 km in width) and according to these figures, it is the world's second largest coral atoll after Christmas Island in the Republic of Kiribati.

The atoll consists of 4 large and around 40 smaller islands located inside the lagoon measuring 224 sq km. There are no settlements in Aldabra, but there is a scientific station with 12 biologists working here while tourists can visit this place by a prior reservation only and their number is strictly limited.

In fact, Aldabra is the only raised coral atoll that has not suffered a harmful human impact. This place is entirely in the power of nature. The overall number of plant and animal species in Aldabra is 307. This kind of diversity has provided the atoll with the title of "one of the crown jewels of the Indian Ocean".  In 1982, Aldabra atoll was designated a UNESCO World Heritage Site, so now the conservation measures are fully and strictly respected. 

A whole world unfolds underwater here: the transparent, almost weightless water allows you to see the reefs in every detail, and the soft sunlight filtering through the surface creates a sense of surrealism.

The coral gardens of Aldabra amaze with their diversity of shapes and colors. Sea turtles swim slowly among the branching and massive corals, like ancient guardians of these places. Their movements are calm and confident, and it seems as if time flows differently here-slower, deeper, more meaningful.

Life teems around the reefs: schools of brightly colored fish change direction in sync, creating vibrant patterns in the water. Occasionally, larger creatures emerge from the depths-graceful stingrays or wary reef sharks, keeping their distance but adding a sense of wildness and true freedom to the scene.

Aldabra reminds us how fragile and valuable the marine ecosystem is. Places like these are rare, and they demonstrate what the ocean can be like without human intervention. This isn't just a journey underwater, but an encounter with a world worth preserving. 

Photos by Oleg Gaponyuk, video by Alexey Tishenko

01 May 2026