From OpenStreetMap Wiki
Jump to navigation Jump to search
Public-images-osm logo.svg dual_carriageway
Dscf0444 600.jpg
Specifies whether a highway is a dual-carriageway (divided) road Edit or translate this description.
Group: Properties
Used on these elements
should not be used on nodesmay be used on waysshould not be used on areasshould not be used on relations
Useful combination
See also
Status: unspecified

The tag dual_carriageway=* has been used to specify whether or not a highway is a dual carriageway or divided highway: a road with a dividing strip or barrier between the traffic in opposite directions. The carriageways in each direction may be divided by an open strip, central reservation or median of grass or bare ground, or by a barrier such as a low wall, fence or hedge. Usually there are two or more lanes in each direction. Note that this tag is not used for motorways.

The great majority of uses of this tag are in Krakow, Poland, though it has been used in a handful of other places.

How to map

Map dual carriageway.png

Add the tag dual_carriageway=yes to a way which is tagged as a highway=primary, highway=secondary or other highway=* feature.

This key is rarely used for highway=motorway, because almost all motorways are dual carriageways. In some regions, highway=trunk are always dual carriageway, but in others this tag is used.

Sometimes dual_carriageway=no is used for a highway=trunk which is not a dual carriageway.

Usually dual carriageway highways, where each direction of travel is divided by a physical separation or barrier, are mapped with a separate way for each direction of travel, and the tag oneway=yes is added. Position the nodes in alignment (as shown in the example).

Also consider adding motorroad=* if foot and bicycle access is restricted, or add access=* restrictions specifically.

See also

  • highway=motorway - a motorway or freeway. While almost all motorways are dual carriageway, divided highways, this tag is not used in that case, since it is implied by the tag highway=motorway.
  • expressway=* - commonly used in the United States to tag a dual carriageway "divided highway" with high-speed design features and limited access to adjacent properties or partial grade separation.
  • motorroad=* - highways that have motorway-like access restrictions. Commonly used in parts of Europe and Japan to specify a road designed for motor vehicle use only.