Viaduct"A viaduct is a bridge composed of several small spans for crossing a valley, dry or wetland, or forming an overpass or flyover. The term is conventional for a rail flyover as opposed to a flying junction or a rail bridge which crosses one feature. The term viaduct is derived from the Latin via for road and ducere, to lead. The ancient Romans did not use the term; it is a nineteenth-century derivation from an analogy with aqueduct. Like the Roman aqueducts, many early viaducts comprised a series of arches of roughly equal length." - (en.wikipedia.org 01.12.2019) Bridge