Rio Paraíba is a significant river system in the state of Paraíba in northeastern Brazil, stretching approximately 222 miles and flowing toward the Atlantic coast. The river is perhaps best known for its expansive estuary — the largest and most important estuary in Paraíba state — where freshwater and saltwater mix to create a remarkably productive and diverse fishery. This estuarine zone supports an extraordinary richness of fish life, with scientific surveys identifying 187 species across 57 families, making it one of the most biodiverse estuarine environments in northeastern Brazil. The lower river and estuary are the primary draw for anglers, offering exciting opportunities to target hard-fighting coastal and estuarine species in a dynamic, tropical environment.