The São Francisco River or Rio São Francisco (Portuguese pronunciation: [sɐ̃w fɾɐ̃ˈsiʃku]) is a river in Brazil. With a length of 2,914 kilometres (1,811 mi), it is the longest river that runs entirely in Brazilian territory, and the fourth longest in South America and overall in Brazil (after the Amazon, the Paraná and the Madeira). It used to be known as the Opara by the indigenous people before colonisation, and is today also known as Velho Chico ("Old Frank").