Key:area

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Public-images-osm logo.svg area
Mapnik area pedestrian.png
Description
Indicates whether a closed way represents an area or just a circular way. Show/edit corresponding data item.
Group: properties
Used on these elements
should not be used on nodesmay be used on waysmay be used on areas (and multipolygon relations)should not be used on relations (except multipolygon relations)
Documented values: 2
Useful combination
Status: approvedPage for proposal

The area=yes tag is required for some closed ways when used to define an Area (polygon); however, for closed ways with other tags there is an assumption that the way defines an area. In some circumstances a closed way may define both a closed polyline and also an area.

Areas can also be described using one or more ways and a relation:multipolygon relation.

If the assumption that a closed way together with other tags defines an area is misleading, area=no can be used to clarify the situation. E.g., leisure=track, sport=running, area=no is just a closed running way.

Important note: a closed way only tagged with area=yes and name=* means nothing in OSM, although it might be rendered on maps by accident.

Used on these elements explained with symbols

Osm element node inactive.svg Osm element node query.svg for nodes the key area is not used Osm element node no.svg
Osm element way inactive.svg Osm element way query.svg for open ways the key area is not used Osm element way no.svg
Osm element closedway inactive.svg Osm element closedway query.svg for closed ways the key area can be used. A closed way without key area or with tag area=no it will demonstrate a Osm element closedway.svg, otherwise if a closed way has the tag area=yes it will be demonstrate a area Osm element area.svg
Osm element relation inactive.svg Osm element relation query.svg for relations area is not used - multipolygons are also marking objects as an area, so area=yes on them would be redundant Osm element relation no.svg

Summary

The following closed ways should be treated as linear features:

  • barrier=*, for thicker hedges or walls or detailed mapping defined using an area add area=yes
  • highway=*, see 'Highway areas' below for more details
  • This list is probably incomplete - please add other cases

Closed ways are assumed to be areas in most other situations, including:

Note that mappers frequently use multiple tags on the same closed way. This can result in the way being used to define both, an area and also a polyline at the outline of this area. For example a closed way tagged landuse=grass and barrier=fence can be interpreted as a fence enclosing an area of grass.

A clean solution would be to create one element for each feature. I.e. tag the closed way with linear feature tags only and add it to a multipolygon to map areas.

See also overview of what is can be considered as implying area status.

Highway areas

Pedestrian areas (for example squares and piazzas) should be formed using a closed-way around the perimeter and be tagged with highway=pedestrian and also area=yes.

Where a road crosses a pedestrian area then a linear way tagged in the usual way should be overlaid across the square. This linear way should shares nodes with the pedestrian area at its entrance and exit from the square.

In the context of roads, area=yes indicates that an area has no street lines within it (i.e., there is no given direction on the area).

Note: There is currently no clear agreement on how highway tag values other than pedestrian should be treated when also tagged with area=yes.

Note: Most pedestrian routing algorithms do not currently route (correctly) across area features, tending to route around the edge or not at all (especially in case of multipolygons). Do not alter your mapping to accommodate such routers.

Proposals

See also