Arches UK - a collection of Nature’s arches and bridges
Arch at Iguazu Falls
Most people visit the world famous waterfalls on the border of Argentina and Brazil but do not notice this natural arch. It is located on San Martin Island in the middle of the Iguazu River. Access to the arch is now restricted and the area is overgrown so that much of the opening is not visible. The Salto Rivadavia Falls can be just seen through the bottom of the opening. It is possible to view the other side of the arch from the Brazilian side of the falls.
The span is about 15 ft and the height is about 25 ft, maybe more.