Iguassu Falls on the border of Brazil and Argentina
is one of thewidest waterfalls in the world -
one and a half miles across.
In flood 13 million litres of water spill over every second.
All the world's great broad waterfalls:
Victoria,
Niagara
and here, Iguassu,
are only found in the lower courses of their rivers.
In their final stages
rivers broaden
and flow wearily across their flat flood plains.
Each wet season here, in Brazil,
the Parana river overflows its banks
and floods an area the size of England.
The Pantanal -
the world's largest wetland.
In these slow-flowing waters
aquatic plants flourish
like the Victoria giant water lily with leaves two metres across.