Rock Island State Park is an 870-acre rustic park at the headwaters of Center Hill Lake and at the confluence of the Caney Fork, Collins, and Rocky Rivers, where two waterfalls and the Caney Fork Gorge define a rugged landscape. Unlike other state park waterfalls, the 80-foot Twin Falls and the 30-foot Great Falls flow constantly because of Great Falls Dam, whose impounded water seeps back through porous limestone and escapes through large cracks to form the falls. The park is known for kayaking, fishing, hiking, wildflowers in March and April, and the Blue Hole, which serves as the spawning ground for walleye in Center Hill Lake. Its historic features include a 19th-century textile mill and one of Tennessee's early hydroelectric plants. The place began as the village of Rock Island, the first permanent settlement in Warren County and its county seat, and logging was the first major local industry. In 1892, Clay Faulkner, H.L. Walling, and Jesse Walling established the Great Falls Cotton Mill, powered by the Great Falls of the Caney Fork River, and also founded the company town of Falls City. A flood in 1902 severely damaged the mill facilities and the mill closed, after which the owners sold the property to the Great Falls Power Company. The Great Falls Hydroelectric Plant was built and began operation on January 1, 1917. The Tennessee Electric Power Company acquired the dam and powerplant in 1922 and expanded operations. The 800-foot-long dam, which still stands, dams the Caney Fork, Collins, and Rocky Rivers to create Great Falls Lake. In 1939, the dam and powerhouse were acquired by the TVA, which later granted the surrounding land to the state, leading to the creation of Rock Island State Park in 1969. The cotton mill, TVA dam, and hydroelectric plant are listed on the National Register of Historic Places, and the dam and hydroelectric plant remain in operation by the TVA.