Tupinambarana

Ilha Tupinambarana is a former fluvial island bordered by rivers of the

Amazon Amazon most often refers to: * Amazon River, in South America * Amazon rainforest, a rainforest covering most of the Amazon basin * Amazon (company), an American multinational technology company * Amazons, a tribe of female warriors in Greek myth ...

system (Amazon,

Madeira Madeira ( ; ), officially the Autonomous Region of Madeira (), is an autonomous Regions of Portugal, autonomous region of Portugal. It is an archipelago situated in the North Atlantic Ocean, in the region of Macaronesia, just under north of ...

, Sucunduri, and Abacaxis) in eastern Amazonas,

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. It has been split into four completely separate parts by natural

channels Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * Channel Country, region of outback Australia in Queensland and pa ...

, just like those isolating it from the

mainland Mainland is defined as "relating to or forming the main part of a country or continent, not including the islands around it egardless of status under territorial jurisdiction by an entity" The term is often politically, economically and/or demogr ...

. The original island stretched from the

municipalities A municipality is usually a single administrative division having municipal corporation, corporate status and powers of self-government or jurisdiction as granted by national and regional laws to which it is subordinate. The term ''municipality' ...

Parintins Parintins is a municipality in the far east of the Amazonas state of Brazil. It is part of a microregion also named Parintins. The population for the entire municipality was 115,363 (IBGE 2020) and its area is 5,952 km2. The city is loca ...

, in the northeast, to

Nova Olinda do Norte Nova Olinda do Norte is a municipality located in the Brazilian state of Amazonas. Its population was 38,026 (2020) and its area is 5,609 km2. The town is located on the banks of the lower Madeira River The Madeira River ( ) is a major ...

, in the southwest. The combined

area Area is the measure of a region's size on a surface. The area of a plane region or ''plane area'' refers to the area of a shape or planar lamina, while '' surface area'' refers to the area of an open surface or the boundary of a three-di ...

of the islands is to 11,850 km², making Ilha Tupinambarana the second largest fluvial group of islands in the world after

Bananal Island Bananal Island (, ) is a large river island formed from the bisection of the Araguaia River, in southwestern Tocantins, Brazil. The island is formed by a fork in a very flat section of the Araguaia; the western stream of the fork retains the n ...

. The largest of the four parts is the 93rd largest island in the world and the 3rd largest island in

. River islands of Brazil Islands of the Amazon Landforms of Amazonas (Brazilian state) {{Island-stub