Yes, there is picnic area
There is a large grass area in front of the Mission before you go in, I do not see a reason why you could not.
To be honest I think you can...I know someone that teaches history in SA and he says on field trips they would picnic all the time
There is no camping
I don't think it would be a good idea to do that
Probobly you can but i didn't see anyone having a picnic there :) (sry bad english)
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