The Pantanal is a tropical wetland and one of the world's largest wetland of any kind. Most of it lies within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay, sprawling over an area estimated at between 140,000 square kilometres (54,000 sq mi) and 195,000 square kilometres (75,000 sq mi). Various subregional ecosystems exist, each with distinct hydrological, geological and ecological characteristics; up to 12 of them have been defined (RADAMBRASIL 1982).
About 80% of the Pantanal floodplains are submerged during the rainy seasons, nurturing an astonishing biologically diverse collection of aquatic plants and helping support a dense array of animal species.
The name "Pantanal" comes from the Portuguese word pântano, meaning wetland, bog, swamp or marsh. By comparison, the Brazilian highlands are locally referred to as the planalto, plateau or, literally, high plain.
