Key:shoulder

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Public-images-osm logo.svg shoulder
15-05-23-Berlin-Sachsendamm-Tesla-RalfR-N3S 7354.jpg
Description
Presence of shoulder in highway Edit or translate this description.
Group: Highways
Used on these elements
should not be used on nodesmay be used on waysshould not be used on areasshould not be used on relations
See also
Status: in use

shoulder=* Indicates the presence of a  shoulder on roads. In some areas, shoulders are also referred to as breakdown lanes.

A shoulder, often serving as an emergency stopping lane, is a reserved lane by the verge of a road or motorway. A shoulder is clearly demarcated from traffic lanes by a continuous white line[1].

Shoulders that are not paved over their entire width are known as soft shoulders (as opposed to hard shoulders), vehicles are expected to partly stop on the grass or gravel verge. Note that a verge with a ditch or shrubbery is naturally not usable as a shoulder. See verge=* for the area beside the road that is not designated as a shoulder.

shoulder:width=* is used to indicate the width of the area designated as shoulders. This information is especially useful for shoulders that are not broad enough to allow any vehicle to safely stop completely beside the traffic lane without obstructing other traffic. In many legislations, it is allowed to ride a bicycle on the shoulder if it is present, which renders even slim shoulders a useful safety feature for cyclists - same for hikers.

Picture from Wikimedia Commons, taken by User:Ralf_Roletschek, licensed Free Art License
Picture from Wikimedia Commons, taken by User:Coolcaesar, licensed cc-by-sa 3.0

Usage

Tag a road with shoulder=yes/left/right/both if it has a shoulder.

If the road has no shoulder, use shoulder=no. This may be useful in situations where data consumers may otherwise assume that there is a shoulder, such as on highway=motorway or even highway=trunk. Furthermore, cyclists and hikers may find it useful to know which rural main roads have neither a sidepath nor a shoulder so that they can avoid it. For this usage, see also verge=*.

Data users should assume that if a generic shoulder=yes is specified and the road is a oneway, it is on the right in countries which drive on the right and on the left side in those which drive on the left (Japan, the UK, Australia, etc.). However, to explicitly specify that there there is a shoulder on just one side of the road, there are two commonly used ways of tagging:

While both kinds of tagging are in use, shoulder=* is used about 10x as often (as of 01/2022):

shoulder=* vs shoulder:left=* shoulder:right=* shoulder:both=*

Unless otherwise tagged, a shoulder should be assumed paved, wide enough to be used as an emergency refuge for cars, and wide enough for through passage by bicycles.

Access permissions are assumed to be inherited from the national defaults for that type of highway, unless otherwise tagged.

For mapping running hard shoulders, see Variable-access lanes.

Refinement

You may want to add further details of the shoulder using normal tags, suitably namespaced. Here are some examples of tags that are in use:

would indicate that the shoulder is 4 meters wide, has a excellently smooth concrete surface, can be used by bicycles and is separated from the road using a solid line.

If the shoulders are different on both sides of the road, consider using the :left/:right suffixes in the keys:

Note that no proposal has been made yet how to tag (the surface of) soft shoulders, i.e. shoulders that are only partly paved. However, in the current usage, shoulder:width=* denotes the entire width of the area designated as a shoulder, not only the paved part.

History

This tag was first proposed in 2010 by Xan and has since gained 'In use' status through widespread usage. It was moved to formal tag documentation in 2016 by Richard after discussion on the tagging mailing list. See initially thread (where Daniel Tremblay comments if there is tag for shoulders), and subsequent threads on the OSM forum and talk-us lists.

shoulder=* is poorly defined in OSM and was used extremely widely, generally without any clarification covering everything from full emergency lane to soft shoulders not fitting even entire car [2][3][4][5].

See also https://community.openstreetmap.org/t/shoulder-tag-is-confusing/5185 where confusion was confirmed, discussed with some attempt to find improvements.

StreetComplete author suggested "There is the hard shoulder (paved), the soft shoulder (unpaved, but maintained) and the verge (grass, not maintained as emergency stopping). Ideally, they should each have their own tag. Currently, at least the first two are muddled together."[6] when commenting on shoulder tagging (shoulder quest shortly after that was disabled in StreetComplete)

References

  1. the exact appearance of a shoulder line actually differs per country, e.g. shoulder lines in Ireland are short yellow dashes and in Angola, they are yellow continuous lines etc.
  2. https://github.com/streetcomplete/StreetComplete/issues/4340#issuecomment-1235667855
  3. https://github.com/streetcomplete/StreetComplete/issues/4617#issuecomment-1307953350 "It would be a lot easier and clearer, if something would only be tagged as shoulder=yes when there is a full-width hard shoulder, or something. But alas, that's not how the tag is seen to be used in the wild"
  4. https://github.com/streetcomplete/StreetComplete/issues/3613#issuecomment-1007439695
  5. https://github.com/streetcomplete/StreetComplete/discussions/4541#discussioncomment-4061198 with Yeah, it's really not in a good shape. That the definition is so blurry only came to the surface after i implemented that quest though. It would be better if shoulder was to be replaced or to be joined by other tags that allow the different types of "shoulders" to be defined more precisely.
  6. https://github.com/streetcomplete/StreetComplete/discussions/4541#discussioncomment-4061198