Key:area

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Public-images-osm logo.svg area
Mapnik area pedestrian.png
Description
Used to mark that a specific feature is a general area.
Group: Properties
Used on these elements
should not be used on nodes
should not be used on ways
may be used on areas
use on relations unspecified
Status: Unspecified
See also Area

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 clarify the situation. E.g., sports=running, area=no is just a closed running way.

Summary

The following closed ways should be treated as linear features:

  • barrier=*, for thicker hedges 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 can result in the way being used to define both a closed area and also a polyline; 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 way for each feature.

Highway areas

Pedestrian areas (for example squares and piazzas) should be formed using an 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.

Proposals