The Cullasaja //  River is a short river located entirely in Macon County, North Carolina. It is a tributary of the Little Tennessee River (and in turn the Tennessee River, Ohio River and Mississippi River), into which it flows near the county seat of Franklin. It originates to the southeast, near Highlands, the county's only other town. It flows from manmade Lake Sequoyah, which is fed by Mirror Lake and other creeks and streams originating on the western side of the Eastern Continental Divide, which runs through the east side of Highlands.
A two-lane highway called Mountain Waters Scenic Byway, which is the combined route of U.S. 64 and NC 28, runs through the Cullasaja Gorge, which is mostly protected as part of the Nantahala National Forest. The U.S. Forest Service has designated this to be a National Scenic Byway because of the river, and its numerous waterfalls, including:
- Bridal Veil Falls, actually from a tributary creek
- Dry Falls, which visitors can walk behind without getting wet
- Quarry Falls, also known as Bust-Yer-Butt Falls
- Cullasaja Falls, the major cascade of falls
The road is known as Franklin Road near Highlands, and Highlands Road near Franklin. Three townships are located in the valley below the gorge: Cullasaja, Gneiss, and Sugar Fork. The Cullasaja's largest tributary is most likely Buck Creek. The most well-known is Peek's Creek, where a catastrophic flood and mudslide occurred in September 2004.
Several former Cherokee towns were located along the Cullasaja River. The town of Ellijay was on Ellijay Creek, a tributary of Cullasaja River. Several Cherokee towns were called Kulsetsiyi (or Sugartown), abbreviated Kulsetsi, including one on Cullasaja River near Ellijay Creek. "Cullasaja" is a variant spelling of the Cherokee town name "Kulsetsi". This Cherokee town's name is also the origin of the name "Sugar Fork".
One of the largest and most important Cherokee towns, known as Nikwasi or Nucassee, was located at the confluence of Cullasaja River with the Little Tennessee River. The town of Franklin grew on the former site of Nikwasi town.