You could purchase at the entrance. However I strongly recommend you purchase in advance online.
You can buy them at the gate!! But, they do encourage online purchases!!
I'm agree with torreyMama and also I suggest to purchase your tickets on line at the same zoo web page because getting them at some other side you still have to get in a long line as anybody purchasing tickets at the gate
You buy the entrance tickets (for a specified entrance time slot) and parking pass online. If you want to park along the street on the north side of the zoo, you dont need a parking pass, but I recommend you arrive early.
Online in advance!
In advance. Advance tickets are needed for all zoos now days.
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