Coari lake (Lago de Coari) at Solimoes river in the Brazilian Amazon rainforest - Solimoes is the name often given to early stretches of the Amazon River from the border of Brazil and Peru to its confluence with the Rio Negro. It is the second longest river in the world with an average discharge greater than the next six largest rivers combined. It has the largest drainage basin in the world, about 7,050,000 square kilometres (2,720,000 sq mi), and accounts for approximately one-fifth of the world's total river flow.