Argentina
These falls are simply magnificent. Bigger and better than either the Virginia or Niagara falls apparently. They can be easily visited from either the Brazilian or Argentinian side by public transport. The Brazilian side was my favourite as you get views of the whole of the falls.
The Argentinian side gives you a more up-close-and-personal view but not one of the grandeur of them. If you have time go to both sides.
The Iguazú falls are stunning and breathtaking. My wife and I were there last year, it was truly spectacular and not to be missed.
Take a bin bag with you to put your clothes in and keep them dry. Then walk around in your swimming costume. It's hot and humid and there's a lot of spray so you can get soaked, but it's wonderful. When you've finished you have dry clothes to put back on.
Apart from the falls, check out the wildlife.
On a couple of evenings either side of the full moon, the park on the Argentinian side is open in the evening. You need to get tickets in advance and they're limited so try early that day. It's really magical and easy to avoid the crowds.
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