Subway (underpass)

An underpass is a crossing under other roads. An underpass is one according to DIN 1076 not one of the tunnels if it has been produced in an open design and no longer than 80 meters. Colloquially is mostly a pedestrian underpass meant.

Underpasses are often built then, if a same-height, secured with a set of traffic lights would be difficult to realize not allow ( for example at a railway crossing ) or topographical conditions other, simpler solutions.