River Tweed River Tweed The River Tweed, or Tweed Water (, ), is a river long that flows east across the Border region in Scotland and northern England. Tweed (cloth) derives its name from its association with the River Tweed. The Tweed is one of the great salmon rivers of Britain and the only river in England where an Environment Agency rod licence is not required for angling. "Tweed" is a British name of uncertain meaning. It flows primarily through the scenic Borders region of Scotland, and eastwards from the settlements on opposing banks of Birgham and Carham forms the historic boundary
Parnaíba River Parnaíba River The Parnaíba River () is a river in Brazil, which forms the border between the states of Maranhão and Piauí. Its main course is long and the Parnaíba River Basin covers . The Parnaíba River rises in the Chapada das Mangabeiras range, and flows northeastward to empty into the Atlantic Ocean, being the longest river entirely located within Brazil's Northeast Region. The middle and upper regions of this river are separated by waterfalls, but is otherwise navigable. The fish species richness in the Parnaíba River Basin has traditionally been considered impoverished, but this has been disproven by recent