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Public-images-osm logo.svg man_made = bridge
2014 Karwina, Darków, Most żelbetowy 01.jpg
The outline of a bridge, grouping together all features for that bridge. Show/edit corresponding data item.
Rendering in OSM Carto
Rendering-man made bridge.png
Group: man made
Used on these elements
should not be used on nodesshould not be used on waysmay be used on areas (and multipolygon relations)should not be used on relations (except multipolygon relations)
Useful combination
See also
Status: approvedPage for proposal

The tag man_made=bridge is used to tag a bridge defined by the outline of the bridge. It is suitable to group together all ways running over that bridge and for holding descriptive tags for that bridge (the object represents the bridge as a whole) and to mark shape of the bridge construction.

How to map

Draw the outline of the bridge as area area and apply man_made=bridge and layer=* to it. The outline should encompass the continuous structure of the bridge.

Additional tags on the man_made=bridge outline:

  • name=* - name of the bridge
  • layer=* - to describe the vertical relationship with surrounding features
  • bridge:structure=* - Load-bearing architecture of a bridge
  • bridge:support=* - Cables and pylons beside the bridge

Ways on and under the bridge:

  • connect the road way ways running over the bridge to the man_made=bridge outline where the ways cross the outline. Mark these ways with bridge=*
  • Do not connect the way ways running under the bridge to the outline
  • Some mappers add covered=yes to segments of highway=* which pass under the man_made=bridge outline, but this is controversial

Delimiting a bridge

Ideally, each end of the bridge should correspond to the point where the bridge's abutment ends and an opening begins below the bridge. This point is clearest in street-level imagery. In aerial imagery, an expansion joint may appear as a thin line running across a road bridge's pavement at the point where you should begin or end the bridge. Parts of the bridge's structure, such as a guardrail or approach slab, may extend beyond this point but are not included in the bridge area. A bridge may have a different surface than the adjoining roadway, for example a wooden pedestrian bridge, making it easier to determine the shape of the bridge. However, a concrete bridge along an otherwise asphalt-paved road may also have a concrete approach slab, so look for an expansion joint if there is one.

Bridges with more than one level

The same as before but the key layer=* should now contain the lowest number of all the features on the bridge. To group together all features of the bridge the proposed relation bridge is now used and the outline tagged with man_made=bridge is added as outline-member to that Relation of the bridge itself should be added to the relation.

A new (alternative) proposal to map multi-level bridges using level=* and location=bridge is described in Proposed features/Simplify man made=bridge mapping#Multi-level bridges

Objects and features on bridges

See proposal objects on bridges for tagging with bridge=* or location=bridge and proposal Relations/Proposed/Bridges_and_Tunnels for using bridge relations.

Bridge ramps

Solid ground bridge ramps can significantly extend the overall space needed to construct a bridge. Like abutments, piers, pylons, etc. they are a bridge supporting structure. Solid ramps leading to a bridge abutment should not be part of a man_made=bridge outline. For significant structures bridge:support=ramp could be used instead on a separate outline, however there has not yet been a proposal for this specific tag.

In some cases the incline of ramps continues, not settling at the abutment. This can be mapped with incline=* on the bridge way. As a rule of thumb, if there is an opening beneath inclined ways, it should be a part of man_made=bridge outline, otherwise bridge:support=ramp. In most cases the abutment serves as a delimiter.


One or more ways, one level

Man made bridge 0.jpg

A bridge represented by only one OSM way, the outline is not drawn yet. The way itself is tagged with bridge=yes and layer=1. Draw the outline.

Man made bridge 1.jpg

A bridge represented by two OSM ways, both of them at the same level. The ways are tagged with bridge=yes and layer=1. The outline is drawn and tagged with man_made=bridge and layer=1. The OSM ways are connected to the outline.

If the bridge has a specific name it would be added to the outline.

Multiple ways, two levels

Man made bridge 2.jpg

A large bridge with two carriage ways and a cycleway running below those. For better visibility only a part of the bridge is shown and the outline is displayed as a red-dashed line.

The OSM ways of the roads are tagged with bridge=yes and layer=2. The cycleway is tagged with bridge=yes and layer=1. The outline is drawn and tagged with man_made=bridge and layer=1. The proposed relation bridge is used to combine all features together and the OSM way of the outline is added as the outline-member to the relation.

The name of the bridge would be added to the relation.

See also