Blue Ridge Parkway tunnels

Blue Ridge Parkway tunnels consist of a total of 26 vehicle tunnels constructed along the 469 miles (755 km) of the Blue Ridge Parkway. One, the Bluff Mountain Tunnel,[1] is in Virginia and twenty-five are in North Carolina.[2]

Blue Ridge Parkway tunnels
Bluff Mountain Tunnel
Overview
LocationBlue Ridge Parkway
RouteBlue Ridge Parkway
Operation
Work begun1930s
Constructedstone and concrete

The design standards specified a minimum impact on the land. The vehicle tunnels were often constructed to reduce excessive landscape scarring that open cuts would have produced. They are used in areas of steep terrain where ridges run perpendicular to the roadway alignment.

North Carolina's more rugged terrain required the majority of the tunnels. Most of the work on the tunnel digging was done by hand and provided by the Civilian Conservation Corps in the 1930s.[3] Little machinery was used with the intention of creating manual labor in depressed economic times. They did have for tunneling truck-mounted water-cooled compressed air drills called "Jumbos." After the initial holes were drilled into the substrata, dynamite was used for blasting away the rock.[4]

Concrete lining was done during construction due to tunnel cave-ins.[5] This concrete lining was first used in the Devil's Courthouse Tunnel. It was later discovered that it enhanced the interior lighting within the tunnel itself. Where done the lining covered about a quarter of the interior structure. An additional benefit was the elimination of moisture entering the tunnel. Moisture in the winter caused ice problems.[6]

The Pine Mountain Tunnel is the longest on the Parkway at 1,434 feet (437 m). Ferrin Knob Tunnel #1 is the first and longest of the triplet tunnels. The local people once referred to ferns as "ferrins." Ferrin Knob Tunnel #2 is located at milepost 401.3 and Ferrin Knob Tunnel #3 is located at milepost 401.5.

The distinctive stone masonry portals now on the parkway tunnels were generally not part of the original construction of the 1930s. They were added later.[7]

Tunnels

The tunnels are listed below by milepost, name, and length. The maximum height is in the center of the tunnel and the minimum height is at the edge stripe.

Note: This table contains data that is significantly different from that provided by the National Park Service on their Blue Ridge Parkway site. The differences are mostly in the tunnel lengths, but also some max/min tunnel heights.[8]

Milepost Name of the tunnel Length Maximum Height Minimum Height Coordinates
53.1 Bluff Mountain Tunnel 630 feet (192 m) 19 feet 1 inch (5.8 m) 13 feet 7 inches (4.1 m) 37.66538°N 79.322866°W / 37.66538; -79.322866 (Bluff Mountain Tunnel)
333.4 Little Switzerland Tunnel 547 feet (167 m) 19 feet 8 inches (6.0 m) 14 feet 4 inches (4.4 m) 35.851638°N 82.085917°W / 35.851638; -82.085917 (Little Switzerland Tunnel)
336.4 Wildacres Tunnel 240 feet (73 m) 19 feet 10 inches (6.0 m) 13 feet 1 inch (4.0 m) 35.829603°N 82.117972°W / 35.829603; -82.117972 (Wildacres Tunnel)
344.6 Twin Tunnel (North) 240 feet (73 m) 21 feet (6.4 m) 16 feet (4.9 m) 35.763598°N 82.169124°W / 35.763598; -82.169124 (Twin Tunnel (North))
344.7 Twin Tunnel (South) 409 feet (125 m) 19 feet 7 inches (6.0 m) 14 feet 7 inches (4.4 m) 35.761875°N 82.170027°W / 35.761875; -82.170027 (Twin Tunnel (South))
349.0 Rough Ridge Tunnel 245 feet (75 m) 21 feet 6 inches (6.6 m) 13 feet 9 inches (4.2 m) 35.726871°N 82.207028°W / 35.726871; -82.207028 (Rough Ridge Tunnel)
364.4 Craggy Pinnacle Tunnel 176 feet (54 m) 19 feet 9 inches (6.0 m) 14 feet 1 inch (4.3 m) 35.701204°N 82.376888°W / 35.701204; -82.376888 (Craggy Pinnacle Tunnel)
365.6 Craggy Flats Tunnel 335 feet (102 m) 19 feet 5 inches (5.9 m) 14 feet 1 inch (4.3 m) 35.687289°N 82.383519°W / 35.687289; -82.383519 (Craggy Flats Tunnel)
374.4 Tanbark Ridge Tunnel 746 feet (227 m) 19 feet 5 inches (5.9 m) 14 feet 1 inch (4.3 m) 35.664224°N 82.461434°W / 35.664224; -82.461434 (Tanbark Ridge Tunnel)
397.1 Grassy Knob Tunnel 600 feet (183 m) 19 feet 2 inches (5.8 m) 13 feet 7 inches (4.1 m) 35.469254°N 82.622304°W / 35.469254; -82.622304 (Grassy Knob Tunnel)
399.3 Pine Mountain Tunnel 1,320 feet (402 m) 19 feet 3 inches (5.9 m) 14 feet 2 inches (4.3 m) 35.449040°N 82.643771°W / 35.449040; -82.643771 (Pine Mountain Tunnel)
400.9 Ferrin Knob Tunnel #1 360 feet (110 m) 19 feet 6 inches (5.9 m) 14 feet 2 inches (4.3 m) 35.456014°N 82.666996°W / 35.456014; -82.666996 (Ferrin Knob Tunnel #1)
401.3 Ferrin Knob Tunnel #2 231 feet (70 m) 19 feet 2 inches (5.8 m) 14 feet (4.3 m) 35.455056°N 82.674271°W / 35.455056; -82.674271 (Ferrin Knob Tunnel #2)
401.5 Ferrin Knob Tunnel #3 323 feet (98 m) 19 feet 5 inches (5.9 m) 13 feet 9 inches (4.2 m) 35.454157°N 82.676163°W / 35.454157; -82.676163 (Ferrin Knob Tunnel #3)
403.0 Young Pisgah Ridge Tunnel 400 feet (122 m) 19 feet 8 inches (6.0 m) 14 feet 6 inches (4.4 m) 35.454444°N 82.700881°W / 35.454444; -82.700881 (Young Pisgah Ridge Tunnel)
403.9 Fork Mountain Tunnel 350 feet (107 m) 19 feet 2 inches (5.8 m) 14 feet 6 inches (4.4 m) 35.450169°N 82.715308°W / 35.450169; -82.715308 (Fork Mountain Tunnel)
406.9 Little Pisgah Tunnel 500 feet (152 m) 19 feet 5 inches (5.9 m) 13 feet 10 inches (4.2 m) 35.421636°N 82.742592°W / 35.421636; -82.742592 (Little Pisgah Tunnel)
407.4 Buck Springs Tunnel 380 feet (116 m) 19 feet 2 inches (5.8 m) 13 feet 8 inches (4.2 m) 35.417720°N 82.747806°W / 35.417720; -82.747806 (Buck Springs Tunnel)
410.1 Frying Pan Tunnel 275 feet (84 m) 19 feet 9 inches (6.0 m) 13 feet 8 inches (4.2 m) 35.390981°N 82.773952°W / 35.390981; -82.773952 (Frying Pan Tunnel)
422.1 Devil's Courthouse Tunnel 350 feet (107 m) 19 feet (5.8 m) 14 feet 2 inches (4.3 m) 35.305332°N 82.895343°W / 35.305332; -82.895343 (Devil's Courthouse Tunnel)
439.7 Pinnacle Ridge 750 feet (229 m) 19 feet 1 inch (5.8 m) 13 feet 10 inches (4.2 m) 35.434901°N 83.033833°W / 35.434901; -83.033833 (Pinnacle Ridge)
458.8 Lickstone Ridge Tunnel 402 feet (123 m) 13 feet 1 inch (4.0 m) 11 feet 1 inch (3.4 m) 35.507822°N 83.187861°W / 35.507822; -83.187861 (Lickstone Ridge Tunnel)
459.3 Bunches Bald Tunnel 268 feet (82 m) 13 feet 4 inches (4.1 m) 10 feet 6 inches (3.2 m) 35.514440°N 83.193087°W / 35.514440; -83.193087 (Bunches Bald Tunnel)
461.2 Big Witch Tunnel 348 feet (106 m) 18 feet 1 inch (5.5 m) 11 feet 3 inches (3.4 m) 35.5178885°N 83.2155379°W / 35.5178885; -83.2155379 (Big Witch Tunnel)
465.6 Rattlesnake Mountain Tunnel 410 feet (125 m) 19 feet 6 inches (5.9 m) 14 feet 5 inches (4.4 m) 35.518671°N 83.269625°W / 35.518671; -83.269625 (Rattlesnake Mountain Tunnel)
466.3 Sherril Cove Tunnel 572 feet (174 m) 19 feet 7 inches (6.0 m) 14 feet 4 inches (4.4 m) 35.511708°N 83.271575°W / 35.511708; -83.271575 (Sherril Cove Tunnel)

See also

 United States portal  U.S. Roads portal  Virginia portal

References

  1. Blue Ridge Parkway North
  2. Virtual Blue Ridge tunnels
  3. Blue Ridge Parkway history
  4. Blue Ridge Parkway tunnels Archived October 24, 2012, at the Wayback Machine
  5. Blue Ridge Parkway Tunnels Archived September 7, 2008, at the Wayback Machine
  6. Historic American Engineering Record, National Park Service, Jennifer K. Cuthbertson, 1997 (Sheet 1 of 28) and Lia M. Dikigoropoulou, 1997, (Sheet 24 of 28).
  7. Blue Ridge tunnels - National Park Service
  8. http://www.nps.gov/blri/planyourvisit/tunnel-heights.htm

Location

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