I've never heard of this. You'd have to contact them and ask.
I visited the zoo about a year ago and not sure about the birthday deal where you get in free or not but I bet if you told them it was your birthday and show them proof of it they either let you in free or give you a good discount. Is a very nice Zoo wished I didn't live so far away I live in Houston Texas quite a ways from Atlanta we visited last year and saw the panda bears
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