Viaduct, << VY uh duhkt, >> is a type of bridge . The term viaduct has no set definition, but it often means a bridge with many spans and supports relative to its overall length. A span is a single length of bridge between supports. The term viaduct may also refer to any bridge that crosses a valley. The word was first used in the early 1800’s, based on the Latin words via (path) and aqueduct an ancient Roman structure that carried water to cities.
Around the world, numerous bridges are called viaducts. They have various lengths and construction types. The Millau Viaduct in France , which was completed in 2004, is a cable-stayed viaduct that crosses the valley of the River Tarn. The total length of the viaduct is over 8,000 feet (2,400 meters). At its highest point, the viaduct’s roadway is almost 900 feet (275 meters) above the river. The Linn Cove Viaduct, completed in 1987, forms part of North Carolina’s Blue Ridge Parkway. The viaduct is a segmental concrete bridge with a total length of 1,243 feet (379 meters). The design was chosen to ensure the least environmental impact on the mountainside beneath.
