Holiday World has very nice camping, water park, emusement park, close by in Santa Claus, IN
http://www.lakerudolph.com/http://www.holidayworld.com/There is also the Lincoln boyhood State park camping. It is across the SR162 road from the Lincoln Boyhood National Memorial.
http://www.in.gov/dnr/parklake/2979.htmhttp://www.in.gov/dnr/parklake/files/lake_lincoln_electric.pdfScales lake park is closest camping in Boonville, IN just 17 miles away.
http://www.scaleslakepark.com/Prices_Rates.htmlSo there is much to see and do all within 25 miles of Interlake off road park. Evansville, IN is just 25 miles to the east of Interlake and has most anything you would want need while traveling (Hotels, shopping mall, airport), you name it.