Found in the middle of the Northern Atlantic Subtropical Gyre (a gyre is a large system of rotating ocean currents)near the Bermuda Islands, the Sargasso Sea is surrounded on all cardinal directions by ocean currents. The only sea on Earth without a land boundary, the Sargasso Sea is bounded to the west by the Gulf Stream; on the north, by the North Atlantic Current; on the east, by the Canary Current; and on the south, by the North Atlantic Equatorial Current. About 1,107 km wide and 3,200 km long, the actual boundaries of the sea vary and roughly correlate with the Azores High Pressure Center.
Named after the free-floating seaweed genus called Sargassum, the Sargasso Sea is home to a high diversity of marine animals such as white marlin, porbeagle shark, and dolphinfish that use the algae for food and shelter. Both Sargassum and Sargasso originate from the Portuguese word “sargaço” meaning grape. The seaweed was named by 15th century Portuguese explorers who thought the air bladders of the Sargassum looked like the fruit.