Iguazu Falls form the largest waterfall system in the world.

An excerpt from the article 31 facts about Brazil

They are the waterfalls of the Iguazu River on the border of the Argentine province of Misiones and the Brazilian state of Paraná. Only 20% of the waterfall area is located in Brazilian territory, and 80% lies in Argentine territory.

The waterfall is stair-stepped. Its width is about 2 km and it consists of 275 separate rockfalls. The largest cascade, called Devil's Throat, is located on the Argentine-Brazilian border. The water here falls from 82 meters - a height greater than Niagara Falls (50 meters).