A viaduct is a specific type of bridge that consists of a series of arches, piers or columns supporting a long elevated railway or road.

Typically a viaduct connects two points of roughly equal elevation, allowing direct overpass across a wide valley, road, river, or other low-lying terrain features and obstacles.

Many viaducts over land connect points of similar height in a landscape, usually by bridging a river valley or other eroded opening in an otherwise flat area.

[6] Where a viaduct is built across land rather than water, the space below the arches may be used for businesses such as car parking, vehicle repairs, light industry, bars and nightclubs.

[7] In Berlin the space under the arches of elevated subway lines (S-Bahn) is used for several different purposes, including small eateries or bars.

[citation needed] In other cases, viaducts were demolished because they were structurally unsafe, such as the Embarcadero Freeway in San Francisco, which was damaged by an earthquake in 1989.

The garden promenade is called the Coulée verte René-Dumont while the workspaces in the arches below are the Viaduc des Arts.