It depends on where you park, but there are many lots that don't have an hourly limit, just a time frame which is all but a few hours in the middle of the night. So there shouldn't be a problem finding a good spot to park. If it's a particularly crowded day you can park further and use the park's green tram to get around. Here is the link to Balboa Park's parking information. https://www.balboapark.org/plan/parking
I think it was 2 hours
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