Clingmans Dome, located near the center of the Great Smoky Mountains National Park just off of US-441 (aka Newfound Gap Road), is the most visited US State highpoint in the most visited US National Park. From the fairly unique lookout tower (often called the "flying saucer") one can see beautiful views of the Great Smoky Mountains, often with clouds nestled between ridge after ridge of mountains. This is the highest peak on the Appalachian Trail. Winter is fun up here as lots of rime ice forms on the tree branches and green plants can be seen completely coated in several millimeters of clear ice. Another good, but crowded, time to visit is during the fall foliage season when the leaves turn all different shades of red, orange, and yellow - quite the feast for the eyes.
The easiest way to visit the summit "flying saucer" is to drive up the US-441 to Newfound Gap (5000') and take the 7-mile Clingmans Dome Road to the parking lot. From there follow a 0.5 mile paved path up to the tower. Another way to reach the summit is to take the 7.7 mile section of the Appalachian Trail from Newfound Gap which parallels the road to the summit. The former is the most popular way to reach the summit for highpointers while the second is probably the most popular way to reach the summit for peakbaggers in the South Beyond 6000 Program. Winter makes this trip more fun since the Clingmans Dome Road is closed and skiing in may be necessary.
Summit Parking Lot and Newfound Gap: This is very straight-forward. Just drive into the park on US-441 passing Gatlinburg (Sugarlands GSMNP Visitor Center & Park HQ) on the north or the Eastern Cherokee Indian Reservation (Oconaluftee GSMNP Visitor Center) on the south. For those coming from the north and east, I-40 is the closest Interstate. Once you get into the park just drive up to the middle, Newfound Gap, and turn west on to the 7-mile Clingmans Dome Road, if you can / want to.
Walk up the paved trail from the parking lot.
Surprisingly None! There are no entrance or backcountry camping fees for this National Park! Perhaps others should follow their lead. Not likely - the reason there are no entrance fees is because of deed restrictions imposed when the park was created in 1934.
There are some useful fee-based developed (aka frontcountry) campgrounds such as the Deep Creek (1800' with 108 sites) and Elkmont (2150' with 220 sites) Campgrounds. Deep Creek is open April 6 - November 1 and Elkmont from March 16 to November 26.
Bears are prevalent so bear bagging is advised. Food storage cable systems are available in certain areas to make this easier.