My brother and I got to Holiday World 2 weeks ago in 3 hours from Dayton, so it'd be about 2 and a half hours from the PKI/Cincy area. They have a great kids area, free parking, free drinks, and good cheap food. I got in, ate 2 meals, played a few games and left only spending about $38. Compare to $48 to park and get into PKI and you'll see why Holiday World is a great little place to hit, and it's good for the kids.