Iguazu Falls are waterfalls on the Iguazu River on the border of the Argentine province of Misiones and the Brazilian state of Paraná. Together they form the largest waterfall in the world. The river flows mostly through Brazil, but most of the waterfalls are on the Argentine side. The first European to record the existence of waterfalls in 1541 was the Spanish conquistador Álvar Núñez Cabeza de Vaca. Steve