Thunderhead Mountain, a prominent western Great Smoky Mountains peak on the Tennessee–North Carolina border, rises 5,527 feet and dominates the landscape above Little River and Bone Valley. Crossed by the Appalachian Trail, it has long been a popular hiking destination, especially for the open views from Rocky Top. Its name, in use by 1859 and associated with fast-changing weather, reflects the mountain’s high-elevation conditions. Thunderhead is formed of ancient Precambrian sandstone uplifted during the Appalachian orogeny. Human activity also altered the ridge, from grazing that created a grassy bald to later park management that allowed much of it to return to forest while preserving trail access.