I'm planning a trip to Argentina in March, it's my first time to South America so i am thinking of getting to know Chile also but I have no idea what is really worth and if the weather would be good for Patagonia.
Need some advise!!

Please be more specific... so I can try to help you.
How long are you staying in Chile / Argentina? your interest? budget?

Yes ask some question so we may know better as to what you are looking for.

I was in these places several months ago and the weather was fine......BUT you know about weather...

I can it was nice and when you go it may rain for two days!!!
Percy

I guess I should be more specific, I was thinking of going a 3-4 days to BsAs then going to iguazu or some other place in argentina worth visiting we are into nature, walking, great views but we want something romantic to... maybe the mountains, making a short car trip and ending in Santiago, what im not sure is that maybe its worth staying in argentina for 2 weeks or having a little bit of Chile is also a good idea.

I quite liked Chile but there is little to see there. Most things worth seeing in South America are in Peru.

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