Why this park
Rock Island State Park sits where the Collins River meets the Caney Fork, at the head of Center Hill Lake. Below Great Falls Dam, the Caney Fork runs through a gorge it has cut in slick limestone.
Great Falls, which gave the dam its name, is a horseshoe cascade that the state's tourism department puts at 30 feet, just below the brick cotton mill the river once powered. Just past TVA's powerhouse, Twin Falls spills from the face of the gorge wall itself, fed by lake water that leaks through the limestone.
That is the picture on our shirt: Twin Falls pouring in white plumes straight out of a wooded limestone bluff into the wide river, with dogwood in spring bloom. To the north, Burgess Falls State Park has a gorge and falls of its own on the Falling Water River.
The story
The name is older than the park. The Tennessee Encyclopedia says the village of Rock Island, which stood upstream of today's park, was the first lasting settlement in Warren County and served for a time as its county seat. When the railroad arrived in 1881, the villagers moved their town to the tracks.
In 1892 Clay Faulkner, H. L. Walling and Jesse Walling opened the Great Falls Cotton Mill above the falls, and with it a company town called Falls City. The mill was three stories of brick, and a turbine turned by water from the Caney Fork drove its machines. Warren County's local history says no other textile mill went up in the county before 1930, and its best-known product was heavy cotton sheeting. In March 1902 a flood swept away its wheel house, and the mill never ran again. The owners sold to the Great Falls Power Company. The mill building still stands, and in 1982 it was listed on the National Register of Historic Places.
A private power company began the dam in 1915, and TVA says it was finished in 1916. It went into service on January 1, 1917. Its lake backed up both the Caney Fork and the Collins, and the water for the turbines is drawn from the Collins side and carried underground to a powerhouse on the Caney Fork downstream.
The lake found another way down, too. Water from the Collins seeped through the limestone and broke out of the gorge face just past the powerhouse. That is Twin Falls. The name seems to come from its two main streams; smaller ones trickle from the wall beside them.
The new lake drew visitors, more of them once the Memphis-to-Bristol Highway, today's U.S. 70S, was finished in the 1920s. TVA bought the dam in 1939 and says it is the only dam it owns outside the Tennessee River's watershed. The state established Rock Island State Park in 1969.
When to go, and what to wear
The temperatures here are NOAA's 1991–2020 normals for nearby McMinnville. Summer is hot, with July highs near 89°F and lows near 68°F. For the heat, the state health department advises light, loose-fitting clothing, sunscreen and plenty of water. The hike back up from the gorge floor is strenuous, so carry more water than you think you need.
Spring is wet. February, March and April each average about 5 inches of rain, and April brings highs near 73°F and lows near 48°F. Dress in layers and pack a rain shell.
Fall is the dry season. October is the driest month, with about 3.2 inches of rain, highs near 73°F and lows near 49°F. In most years the leaves turn in late October, though the timing shifts with the weather. Bring a sweatshirt for an early start.
Winter brings January highs near 51°F and lows near 31°F, and December is the wettest month of the year. Wear a warm jacket, a hat and gloves at the overlooks.
In any season, wear sturdy shoes that grip. The park describes the gorge as slick limestone bedrock and the trail down from the Old Mill as steep, wet and rocky, and it advises against flip-flops and other slip-on shoes.
Know before you go
- Water in the gorge can rise suddenly when the dam opens its floodgates or the powerhouse releases water. Sirens are in place, but the park warns that major releases can come without warning. If the water rises or a siren sounds, leave the gorge at once.
- The gorge and its trails close whenever the dam is spilling or a release is likely that day, sometimes without notice; TVA posts its release schedule online.
- Swimming and wading are never allowed, whatever the releases, at Twin Falls or anywhere from TVA's powerhouse downstream to the main beach boat ramp, and swimming is prohibited everywhere above Great Falls. When the gorge is open, the park names two swimming holes in it, the Cold Hole and the Warm Hole. When it's closed, use the sand-silt swim beach on the Caney Fork. No lifeguards are on duty, and never jump into water of unknown depth.
- The park asks that you see Twin Falls from the Powerhouse Road overlook.
- Check Rock Island State Park's page for hours, fees and current conditions.
Sources: Tennessee Encyclopedia, "Rock Island State Park" (Carroll Van West); Tennessee Valley Authority, "Great Falls Reservoir" and environmental review "Rock Island State Park Easements" (2020); National Park Service, National Register of Historic Places, Great Falls Cotton Mill (1982); Jane Hembree Crowley, "Great Falls Cotton Mills," Warren County TNGenWeb, after Eugene Wiseman, The Warren County Story, and Arthur Weir Crouch, The Caney Fork of the Cumberland (1973); Tennessee Department of Tourist Development, "Rock Island State Park" and Amanda Burton, "Tennessee Waterfalls Worth the Hike" (2025); Tennessee State Parks, Rock Island reservations page and "Exploring History at the Falls City Cotton Mill" (2025); Tennessee Department of Health (2025); NOAA, U.S. Climate Normals 1991–2020, McMinnville station; Elizabeth Hutchison Hicklin, Garden & Gun (2024); GoWaterfalling, "Twin Falls"; WSMV (2025 and 2026); Wikipedia; Rock Island State Park, tnstateparks.com.
