Colombia/Brazil Chile/Argentina Argentina/Brazil Bolivia/Peru
Brazil/Chile Bolivia/Chile Argentina/Chile Colombia/Chile
Mosel Rhone Volga Seine
Europe Africa N. America S. America
Orange Okanvango Zambezi Niger
Nile Congo Amazon Zambezi
Colombia/Brazil Chile/Argentina Bolivia/Brazil Bolivia/Peru
Argentina Brazil United States Venezuala
Okanvango Delta Vatnajokull Angel Falls Ross Ice Shelf
Texas California Virginia Florida