Like others said, you need to get a permit from the city which is pretty inexpensive. I did the same thing for my wedding at Treaty Oak. Worked out great
It's not "rented" per se, but you pay a permit fee to the city for use of City Recreation Area. Your permit allows you use of the area for the day, and acts as a reservation, so that others cannot use the area for another event, but your event is technically not private, as it is being held in a public park and can still be accessed by the public. You will also need to pay the permit fee and reserve the park a minimum of two weeks prior to your event.
You have to get a permit from the city.
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