Rock Island State Park Campground Professional Review and Guide
"These days, the hand of man is often seen as a destructive force in nature. Here at Rock Island State Park, human forces unintentionally created what many Tennesseans (the author included) consider to be the state’s prettiest waterfall. Here's the story. In 1915, Tennessee Electric Power Company dammed the Caney Fork River. This dam backed up the Caney Fork and the nearby Collins River, creating Great Falls Lake. This raising of the water level forced water from the Collins River through caves that emerged on a rock face of the Caney Fork River.
Since then, and to this day, water courses through the caves, then makes a 300-foot-wide, 80-foot drop over a rock bluff into the Caney Fork River. This drop is known as Twin Falls. Great Falls, the lake’s namesake, is actually a different scenic cascade within the park boundaries. This watery beauty is only part of the picture, however. A tent-only camping loop, trails, swim beaches, and more make Rock Island State Park a great destination."