Solimões (Portuguese pronunciation: [soliˈmõjs]) 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.
Further upstream from the border, the name of the river seems to depend on the speaker. Brazilians may either continue to call it the Solimões or refer to it as the Rio Marañón -- a name which Peruvians usually only apply further upstream, before the Marañón and the Ucayali join to create what they, and most of the countries in the world (excluding Brazil), call proper the Amazon river.