No charge, I believe it's first come first serve for the picnic shelters. They're open every day during the warm weather season.
Kingsport City Parks and Recreation would be the people to contact. I suggested an edit for the hours listed. It should be daylight to dusk, but there isn't that option to choose when suggesting an edit.
To reserve a shelter, it $20 per hour. If you are there having a party and someone shows up with it reserved, you will have to move. If you are interested in reserving, you can contact Kingsport City Parks and Recreation.
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