You would need to contact your human resources department with the city to confirm if you have a benefit to the city zoo. One of my past employers in Philadelphia provided us with a membership at a discounted price as a benefit but again was offered by the employer, would advise to contact the employer hr.
On the website it shows discounts. I would look at family passes. If you plan to go more than 1 time.
If he or she has the zoo membership, there are a lot of benefits such as bringing certain number of guest, visiting the zoo throughout the year except winter naturally. And certain discount for meals and drinks (not all).
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