Monster Ball Adults Only Climb takes the Halloween fun up high at The Adventure Park at Nashville, with ziplines, climbing and a spooky grown-up twist. The kids get the candy this time: this one is strictly for adults, 18 and up. Think of it as flying through the night like a bat, with plenty of thrills along the way. The Adventure Park is a wooded course with rope and zipline challenges, so it's an easy spot for an adrenaline rush surrounded by trees.