There are three major tracks to enjoy in this terrific park. The lower circuit (views from the bottom of the falls, 1.4 km long), upper circuit (top of the falls, 1.8 km), and Garganta del Diablo (train ride and 1.1 km walk). I recommend starting from the lower circuit so you get to admire the full length of waterfalls and get a little wet.
The Iguazu Falls will sweep you off your feet and leave your jaw dropped for days. It was by far the most impressive nature site we have seen in our travels. An area at the borders of Brazil, Argentina and Paraguay contains 275 waterfalls which vary in size and speed of water flow. And they have lush, tropical forest where hundreds of birds fly and capuchin monkeys lurk in trees.