The Rio São Mateus is a significant river in the state of Espírito Santo, Brazil, flowing for 224 kilometers. It is formed by the confluence of the Cricaré River and another tributary near the city of São Mateus, after which it continues northward. Historically, the river served as a vital transportation route for agricultural products like flour and sugar. For paddlers, the river offers access points and boat ramps, with specific launch and takeout locations available for trip planning. The river passes through varied landscapes, including areas near the coastal Abrolhos National Marine Park and Guriri Beach, suggesting a mix of inland and coastal-influenced environments. The river's character is defined by its role as a historical conduit and its connection to the regional ecosystem. The presence of designated access points indicates it is a recognized waterway for recreational use. Paddlers should be aware of its historical and ongoing importance to the local communities along its course.