Guairá Falls were a series of immense waterfalls on the Paraná River along the border between Paraguay and Brazil. The falls ceased to exist in 1982 when they were inundated by the impoundment of the Itaipu Dam reservoir. While published figures vary, ranging from 13,000 m3 (470,000 cu ft) per second to 50,000 m3 (1,750,000 cu ft) per second, Guaíra's flow rate was among the greatest of any then-existing falls on Earth.

Salto del Guairá is a city in Paraguay. It is the capital of the department of Canindeyú. The city is located about 200 km north of Ciudad del Este. It borders the Brazilian municipality of Guairá, across the Paraná River which marks the border between Paraguay and Brazil.