I know you. Can rent it for a wedding, but I'm not sure about the ten p m. Part. Just ask, and if your wedding is to be during the summer months all the better. The days are longer, so there"s no problem with the park getting getting too dark to traverse, which is a problem you might have in the later hours , and it might be a safety issue with the park.
If you want to reserve a picnic shelter or part of the park for a private group, there is a small day-use fee. And I believe you can make the reservation by calling the park itself, or going on the pge website.
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