The grounds are open to the public when the mansion is not hosting a private event. There are signs posted when the grounds are closed. There are no picnicking places on the mansion grounds. Wadsworth falls state park is a great alternative spot.
Generally it's a wedding venue and less of a day-picnic place, there are neighboring parks, like wadsworth falls that are good for picnicing
They have a huge lawn, but it would probably be trespassing.
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