The AT runs 72.371 miles in the Great Smoky Mountain National Park. The cumulative climb from Fontana to Davenport Gap is about 20,000 feet (about 278 feet per mile). The mileage profile below is based on Robert Lochbaum's wheel-measured trail data (2007). Bob's data is also used in the "brown book", Hiking Trails of the Smokies. (GPS track distance with elevation adjustment: 71.913 miles. GPS distance is typically shorter due to discretization error.)
Mile elevation Feature 0 1727 Fontana/GSMNP boundary AT mile 164.4 0.7 1890 Lakeshore Trail 4.0 Shuckstack 4.4 3670 Lost Cove Trail/Sasafras Gap/Twentymile Trail 5.3 3663 BC113 Birch Spring campsite 7.5 4466 Gregory Bald Trail 7.6 Doe Knob 9.0 3842 Ekaneetlee Gap lowest gap on Smokies crest 10.7 4570 Mollies Ridge Shelter 10.9 Devils Tater Patch 12.8 4089 Big Abrams Gap 13.9 4360 Russell Field Shelter/Trail 16.0 Mt Squires 16.8 4915 Spence Field Shelter/Eagle Creek Trail/Bote Mtn Trail 17.1 4930 Jenkins Ridge Trail 17.9 Rocky Top 18.6 5527 Thunderhead 21.2 4527 Starkey Gap 22.0 Sugartree Gap 23.0 4880 Derrick Knob Shelter 23.3 4770 Greenbrier Ridge Trail 25.4 Cold Spring Knob 25.7 4951 Miry Ridge Trail 25.9 Buckeye Gap 28.6 5460 Silers Bald Shelter 28.8 Silers Bald 29.0 5432 Welch Ridge Trail 30.3 5505 Double Spring Shelter 30.9 5756 Goshen Prong Trail 32.8 6517 Clingmans Dome bypass Trail 33.1 Clingmans Dome Trail 33.2 6643 Clingmans Dome 35.2 Collins Gap 36.2 Mt Collins 36.3 5962 Sugarlands Mtn Trail 36.5 5870 Mt Collins Shelter 36.6 5888 Fork Ridge Trail 39.3 5258 Indian Gap/Road Prong Trail 41.0 5022 Newfound Gap AT mile 204.7 42.7 5817 Sweat Heifer Trail 43.5 Mt Ambler 43.7 6034 Boulevard Trail 44.1 5920 Icewater Spring Shelter 45.5 5401 Dry Sluice Trail 47.6 5221 False Gap 49.1 Laurel Top 51.5 5280 Hughes Ridge Trail/Pecks Corner Shelter 52.4 Eagle Rocks 54.3 Mt Sequoyah 55.9 Mt Chapman 56.7 5920 Tricorner Shelter/Balsam Mt Trail 58.0 Mt Guyot 59.0 Old Black 60.5 5788 Snake Den Ridge Trail 62.8 4688 Camel Gap Trail 64.0 Cosby Knob 64.4 4740 Cosby Knob Shelter 65.1 4242 Low Gap Trail 67.2 4963 Mt Cammerer Trail 69.5 3465 Lower Mt Cammerer Trail 70.4 2879 Chestnut Branch Trail 71.5 2600 Davenport Gap Shelter 72.4 2003 Davenport Gap AT mile 236.0Also see AT trail elevation profiles or shelter elevation profile and Smoky Mountain trails elevation profiles. You can draw tracks and get elevation profiles using the AT google map or the GSMNP google map.
The highest point on the AT is 6613' just NE of Clingman's Dome at Smokies mile 32.9 (35.56313 -83.49799).
Running the crest: 2009 and 2011
AT shelters 
with elevation profiles between shelters based on this
elevation data
AT lat,lon,elevation data from USGS DEM
GSMNP clickable trail map
GSMNP landforms and campsites
maps and GPS waypoints
clickable Google GSMNP map/topo with
campsites/landforms/trails (2007 data)
2012 Smokies GPS elevation survey TN/NC
LiDAR
Cumberland Trail elevation profiles