Iguasu Falls (Foz de Iguacu) on the Iguacu river, near the juncture of Argentina, Paraguay and Brazil, is the world's greatest in terms of volume of water flowing. Across the river and upstream is Paraguay's Ciudad del Este, formerly Ciudad Stroessner. C del E is now a quasi-legal duty-free zone for prosperous Brazilians, who vacation at Iguacu so they can shop for cheaper appliances and electronics in Paraguay.