Hartland Rapids

Also known as Sumner Falls, this is a series of ledges sprawled out across a wide section of the Connecticut River and should be attempted only by experienced whitewater paddlers who have already scouted them. This is the sole stretch of the river which is still in its natural state, the Connecticut being reduced to a series of power pools by 12 dams.

http://www.americanwhitewater.org/content/River/detail/id/3606/