- Pigtail bridge
A pigtail bridge is a type of
road bridge , where the road curls and passes over itself. This allows the road to negotiate sharp changes intopography in limited space. Most pigtail bridges are found in theBlack Hills ofSouth Dakota , where they were first built. However the use of aspiral road to negotiate a steep slope is nothing new, for instance having been used in 1904 inWarsaw , where the Wiadukt Stanisława Markiewicza in Ulica Karowa connectsKrakowskie Przedmiescie to river level.The pigtail bridge design was invented in 1932 by Cecil Clyde Gideon, the self-taught superintendent of
Custer State Park turned highway designer. He called them “spiral-jumpoffs”. During the planning forIron Mountain Road , there was a need to negotiate sudden elevation drops while preserving natural features for this scenic highway; the corkscrew design allowed for a spectacular - although expensive - solution to this problem. In order to blend the bridges with their surroundings, natural materials such as local timber were used.Most pigtail bridges were built by the
Civilian Conservation Corps in the 1930's.Notable pigtail bridges
* Three bridges on
Iron Mountain Road
* One bridge onSouth Dakota Highway 87 inWind Cave National Park
* A well-traveled pigtail bridge on US Hwy 441 between Gatlinburg, TN and Cherokee, NC at Bearpen Hollow in the [http://en.wikipedia.org/wiki/Great_Smoky_Mountains Great Smoky Mountains Nat'l Park] and probably more familiar to Eastern US drivers
* The C-345 near Málaga, SpainReferences
* Bernie Hunhoff, " [http://www.southdakotamagazine.com/?p=962 The Man Who Designed the Pigtails] ", South Dakota Magazine, 27 July 2006,
* Jim Pisarowicz, " [http://www.nps.gov/archive/wica/Pigtail_Bridge.htm Pigtail Bridge] ,Wind Cave National Park ,National Park Service
* Brochure, " [http://www.fs.fed.us/r2/cdi/portfolio/interpretive_products/publications/pdfs/PNSB.pdf Welcome to the Peter Norbeck Scenic Byway] ",United States Forest Service
* " [http://www.sddot.com/pe/bridge/docs/Missouri_River_Bridges_1920.pdf Missouri River Bridges of South Dakota, 1920 to 1980] ", interview of Kenneth R. Scurr, Former South Dakota Bridge Engineer, by Emory Johnson, So. Dakota State University
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