Represa de Sobradinho — known locally as Lago de Sobradinho — is one of the largest artificial reservoirs in the world, stretching across the semi-arid sertão of Bahia state in northeastern Brazil. Formed by the damming of the Rio São Francisco, this massive impoundment sits approximately 50 km from Petrolina and has been in commercial operation since 1979. The reservoir plays a critical role in regulating water flows throughout the entire São Francisco River Basin, which drains portions of Minas Gerais, Bahia, Goiás, Pernambuco, Sergipe, and Alagoas. The São Francisco — affectionately called "Velho Chico" (Old Frank) by locals — is the longest river entirely within Brazil at 2,914 km, and Sobradinho sits at the heart of its northeastern reach. The sheer scale of this reservoir, combined with the rich aquatic biodiversity of the São Francisco system, makes it a compelling destination for anglers seeking trophy freshwater species in a dramatic, sun-baked landscape.