Very impressive and spectacular. Gigantic rocks have worked themselves to the surface of the earth, to split apart there. You can imagine the sound effects by just looking at the results.
As you approach it over gently rolling pampas, that impression is very striking. There's nothing that leads up to it - suddenly the mountains pop up there, like a wart. But a what a beauty of a wart!
First thing you notice when getting closer is the growing presence of guanacos. A relation of the camel-like llama, these beasts have been hunted almost to death for fur and meat (don't forget the sport!) to make an amazing come-back as soon as they started being protected (not very long ago.) Wonder how the sheep-ranchers feel about them.
Darwin remarks on all those dead trees. They're all over. Obviously some are the result of fires, but certainly not all
some more weird fauna, to get it over with: ñandi, colleague, hare