I feel if it is two getting married, a minister and 5 guests without planning to have music or impede on someone walking in the park you would be fine. Now if you need reserved parking, reserved eating area, and a place for seating during the ceremony I would call Five Rivers, as this would definitely impact people visiting the recreation area. But, as Stephen said, the best thing to do is call them.
Cox has a number of venues available for weddings depending upon what you have in mind. The cost varies depending upon what you need. I recommend calling them and talking with them about the details.
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