In my opinion, one of the most beautiful places in South America is Los Alerces National Park, a few hours drive south of Bariloche.
The combination of glacial lakes and streams, lush forests, and snow-capped peaks makes for stunningly beautiful scenery.
This photos shows a confluence of two rivers of crystal clear water. The figure in the water on the right is a fly fisherman.
...and we think we have beautiful fishing spots in Montana!