Iguaçu (Portuguese) or Iguazú (Spanish) Falls are on the border of Brazil and Argentina and close to Paraguay.
Below find two slide shows, one from the Brazilian side of the falls and another from Argentina.
The first presentation is longer, because I had more time to spend on the Brazilian side. I caught a bus across the street from my hotel, which took me to Brazil's lovely welcome center with colorful buses to take one to the actual falls. One descends and climbs lots of steps and takes wooden or metal walkways to see the falls. Afterwards, I walked across the road to the Bird Park where one can enter cages with exotic birds. (See the Bird Park slideshow HERE.)
The following day, I caught a bus from Foz do Iguaçu, Brazil, went through customs at the border, exchanged dollars for pesos, took a bus to the city of Puerto Iguazú, then another to the falls. It was a rainy day, and not as nice for taking photos as it was the previous day.
By the way, even when it was not raining, the overspray from the falls, even when not close to them, is enough to get one quite wet. The first morning had been cool, so I threw a nylon parka into my knapsack, not even thinking I would need it to stay dry, but it came in handy, although plastic raincoats were on sale on both sides of the falls.
The Argentinean falls were fun because of the coati, an animal of the racoon family, which roamed everywhere. (I have seen videos of coati on the Brazilian side, too, but I didn't see any myself.) In Argentina, they wandered among the tourists and were quite tame. Despite many signs about not feeding the animals, I saw many tourists doing so.
Some of the Argentinean falls were wide and spectacular like the Brazilian ones, but some were narrow and surrounded by vegetation. I felt more as if I were in a rain forest than when viewing the Brazilian falls. But they were both spectacular to see. (Be sure to check out the very short video at the bottom of this post.)
These falls just go on and on. They were one of the highlights of my trip.
I had always regretted missing Iguaçu when I lived in Brazil 40+ years ago, so I knew I had to visit there on this trip ---my first time back since 1969.
The sound of the roaring water is almost deafening. I included a very short (27-second) You Tube video to demonstrate the sound and the enormous amount of water rushing over the falls. This is just one small section of the falls. Imagine this amount of water multiplied by perhaps 100 rushing over the falls.