Guanabara Bay (Harbor of Rio de Janeiro)

Few cities owe their image to a single body of water as completely as Rio de Janeiro owes its to Guanabara Bay. Ships enter through a narrow mouth guarded by Sugarloaf Mountain, and inside the water opens into a broad bay ringed by granite domes, forested peaks and beaches, with the statue of Christ the Redeemer watching from Corcovado. When Portuguese navigators arrived on January 1, 1502, they mistook it for the mouth of a river and called it the River of January, the name the city still carries. In 1997 CNN named the Harbor of Rio de Janeiro one of the Seven Natural Wonders of the World, the only one shaped as much by a city as by nature.

The bay is an estuary drowned by the sea, about 31 kilometers long and 28 wide, covering roughly 384 square kilometers. Its entrance between Sugarloaf on the Rio side and the Santa Cruz fortress on the Niterói side is only about 1.5 kilometers across. Inside, the water is shallow, averaging under 6 meters, though channels near the mouth reach about 50 meters. More than 130 islands dot it, the largest being Governador, home to Rio's international airport, and Paquetá, where cars are banned. The Rio–Niterói Bridge spans the bay for 13.3 kilometers. Mangroves fringe the northern shore at Guapimirim, and millions of people live in the municipalities around it, among them Rio de Janeiro, Niterói, São Gonçalo and Duque de Caxias.

The Tupi peoples called the bay Guanabara, often glossed as bosom of the sea. French Huguenots founded a colony on one of its islands in 1555, and the Portuguese drove them out and founded Rio de Janeiro on its shore in 1565. The harbor carried gold, sugar and coffee, and as the main port of entry for enslaved Africans in the Americas, it marked Brazil's history deeply. It hosted the Portuguese court from 1808 and was Brazil's capital until 1960. The hills around the bay form part of the Rio de Janeiro World Heritage Site, inscribed by UNESCO in 2012. Untreated sewage and industrial waste remain the bay's great problem, and cleanup pledged for the 2016 Olympics fell short, though new sanitation works since 2021 have reopened some beaches.

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• Christ the Redeemer
  Rio de Janeiro's Art Deco Christ, arms spread above the city from Corcovado overlooked by