The Falls of the Ohio lower site provides many fun playspots during the Summer months. The lower site is located off Harrison Avenue in Clarksville. The putin is the George Rogers Clark boat ramp.
Be prepared to duke it out with the fishermen. This area is not only rife with play potential, but home to some of the biggest, scariest fish you'll ever see (unless you visit the Amazon!).
Also see the
Upper Falls of the Ohio.
Also check out
Falls of the Ohio State Park. Among the big deals there are the fossils in the old seabed.