JA:OSM tags for routing

What Map_Features are stored in OpenStreetMap that you can use when routing?

This page gives a guideline to what existing and regularly and consistently used tags should be interpreted for routing and how they are to be interpreted. If any meaning of a tag is added that affects routing then that tag and its meaning shall be added here.

Contents 1 Oneway 2 area=yes 3 Name 4 Is inside/outside 4.1 City 4.2 Zip-Code 4.3 Country 4.4 Roads 5 Traffic signals 6 Access-Restrictions 7 Turn-Restrictions 8 Max speed 9 Routing to postal addresses 10 Further Links

Oneway

A way is oneway if and only if: (case is not relevant)

• oneway=yes or
• oneway=true or
• oneway=1 or
• oneway=-1 (denotes opposite direction to node order) or
• junction=roundabout or
• highway=motorway or (This is currently being discussed)
• highway=motorway_link

and

• "oneway"!="no" and
• "oneway"!="false" and
• "oneway"!="0"

("oneway"!="no" has precedence over "highway"="motorway")

area=yes

The area=yes tag can be used for tagging a area such as a market square as an area which means that together with highway=residential it can be navigated by car, in any direction, and cutting across from any points. (the highway tag conventionally does not apply to an area)

The use has been approved, and promoted onto Map Features, but clearly this tag will be problematic for routing, especially if developers/tools are not aware of it.

Name

The following tags may contain the name of a street:

• name=*, "name:<2digit-language-code", int_name, ...
• ref=*, "nat_ref", "loc_ref", "int_ref"

See: naming

There is also an external xml-webservice that can do searches for you.

Is inside/outside

The following tries to give a definite algorithm for resolving +

• if a location is inside a given city/country/zip-code +
• what city/country/zip-code a given location is in +

We are trying to cover all currently approved and used taggings for this and rate them in a deterministic order of importance. So you need not search everything to implement your algorithm.

City

A way is in a city/suburb/zip-code/... if and only if:

• a) It is individually tagged as is_in=*.
  • b1) It is inside an area tagged as place=*
  • b2) It is inside an area tagged as boundary=administrative and admin_level=8
• c) It is not inside such an area but a node tagged as place=* is inside an area with landuse=* with a value other than "farm", "quarry", "forest" or "water" and the way is inside the combination of that polygon and all intersected or "nearby" polygons of this kind (difficult to implement but a good autotetection.).
• d) None of these but the nearest point tagged as "place"= is less then XX km away.

For case (d) sensible values are:

1. is tagged the radius is given by a radius-tag in meters or kilometers.
2. if not tagged, these are sensible default-values:

Tag	Element	Radius
place=continent		n/a, continents must have borders
place=country		n/a, countries must have a defined border-polygon
place=state		n/a, states of countries must have a defined border-polygon
place=region		500 km
place=county		200 km
place=city		10 km
place=town		5 km
place=village		1 km
place=hamlet		300 m
place=suburb		300 m
place=island		n/a, islands must have a defined coastline-polygon

Zip-Code

Country

This topic is currently for debate on the OSM-Dev mailing-list.

The current progress is documented in Tagging Country Borders.

Roads

Only ways or areas marked with the key highway=* or junction=* are a road that a car, bike or pedestrian can navigate on.

Beware for the values "footway", "pedestrian", "steps", "gate", "stile", "cattle_grid", "viaduct" and limit the usage of "ford", "service"/"services"

Traffic signals

You should limit the expected speed when crossing nodes tagged highway=traffic_signals, highway=stop or barrier=toll_booth as well as incline=*.

Access-Restrictions

The default access-restrictions for each vehicle- and highway-type are documented in /Access-Restrictions.

To compute access restrictions in the presence both of default values and explicit values, see Computing access restrictions.

Turn-Restrictions

Restrictions to prohibit certain kinds of turns at intersections are documented in Relation:restriction.

Max speed

The default maximum-speed if not given by maxspeed=* is now documented on on this page.

Routing to postal addresses

See addr:*=* for details on addresses.

Further Links

• project on WheelChair Routing (in German)
• project on routing for blind persons: LoroDux