What is the name of the famous waterfall on the border of Argentina and Brazil?

The famous waterfall on the border of Argentina and Brazil is Iguazu Falls. It is a vast waterfall system on the Iguazu River, where the river forms part of the international boundary.

Rather than being one single curtain of water, Iguazu consists of roughly 275 separate cascades spread across about 2.7 kilometres. Most of the individual falls are on the Argentine side, while Brazil offers broad panoramic views. The spectacular Devil's Throat is the system's best-known section.

The name comes from Guarani or Tupi words meaning “big water.” The falls divide the Iguazu River into upper and lower sections before the water flows into the Paraná River. During floods, many separate cascades can merge into a nearly continuous wall of water.

Visitors reach the falls through national parks in both countries. Iguazú National Park in Argentina and Iguaçu National Park in Brazil are both UNESCO World Heritage Sites, recognized for their scenery and subtropical biodiversity.