The South Atlantic's only atoll is a remote, volcanic sanctuary for marine life

Countries & Cities · Published 29 September 2026 Swipe more like this →

In short: Located 260 kilometers from the Brazilian coast, the Rocas Atoll stands as a unique geological anomaly in the South Atlantic. This volcanic, coralline structure serves as a vital feeding ground for sharks, turtles, and dolphins, remaining largely untouched by human interference due to its extreme isolation and protected status.

The Rocas Atoll is a rare geological feature, representing the only atoll found within the South Atlantic Ocean. Situated roughly 260 kilometers northeast of Natal and 145 kilometers west of the Fernando de Noronha archipelago, the structure is defined by its volcanic origins and subsequent coralline growth. The atoll forms an oval shape, measuring 3.7 kilometers in length and 2.5 kilometers in width, with a central lagoon reaching depths of up to 6 meters.

The landmass consists of two distinct islets, Cemitério Island and Farol Cay, which together cover a total area of 0.36 square kilometers. Farol Cay, the larger of the two, contains the highest point of the atoll—a 6-meter sand dune. While the islets support a modest ecosystem of grasses, bushes, and palm trees, the primary inhabitants are diverse, including various species of birds, crabs, spiders, scorpions, and beetles. The surrounding coral ring is nearly continuous, broken only by two narrow channels that allow water exchange.

In 2001, UNESCO designated the site a World Heritage Site, recognizing its critical role as a feeding ground for marine biodiversity. The area is managed as the Atol das Rocas Biological Reserve, where human activity is strictly limited to scientific research. Despite its ecological importance, the atoll’s remote location presents a significant challenge for researchers, resulting in a limited number of comprehensive studies. The site also features a Brazilian Navy lighthouse, which has been in operation since the 1960s, located near the ruins of an older, derelict structure dating back to 1933.

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