From OpenStreetMap Wiki
Jump to navigation Jump to search
Public-images-osm logo.svg turn
Zeichen 297.svg
用于指定导向车道的指引方向。 编辑此说明
组: 属性
状态:已批准Page for proposal


Help (89606) - The Noun Project.svg


  • from the first indication via road markings, signposts or similar indications (including traffic being guided by solid lines into a particular turn, e.g. "turn pockets")
  • to the junction or the completion of merge.

This key is mostly used with the :lanes suffix (turn:lanes=*), to tag indicated turn markings for individual lanes. See the section Turning indications per lane on this page.


When turns apply similarly to all lanes in the same direction (or when there's a single lane per direction)
Without a ":forward" or ":backward" or ":both_ways" direction suffix, the turn=* applies to both directions, or to the forward direction of oneway=yes highways (the same direction as the OSM way is drawn), or the backward direction of oneway=-1 highways (the reverse direction as the OSM way is drawn). You usually don't need to append such direction suffix to most oneway highways, unless the other direction applies to specific vehicles allowed to use the highway in the opposite direction (e.g. for some bus service lanes or cycleways, possibly on the same shared single lane, usually with a priority or with trafic control devices to alternate the direction when needed for these vehicles, or with special warning signals).
To specify different turn indications for each lane when there are multiple lanes in the same direction (see below)
In most frequent cases these tags are used to specify turn directions for separate lanes, but on bidirectional highways with separate single lane per direction, you can just separate the forward and backward directions. If you use the ":lanes" suffix, the number of values specified separated by vertical lines (|) must match the number of lanes according to their direction.

In addition to the individual values listed below, you may also indicate multiple directions by separating them in any order with a semicolon (;). If you specify multiple values any one of separate lanes, the lanes order must be preserved and must still be separated by vertical lines (so a lanes tag whose value is given as turn:lanes=a1;a2|b1;b2 specifies values for two lanes, not three, each lane having two values, and is equivalent to turn:lanes=a2;a1|b2;b1 but not to turn:lanes=a1;b2;a2|b1).

Value Description Road marking example Signpost example
left left turn (only) Richtungspfeil Links.jpg Left only.svgFrance road sign B21c2.svgFrance road sign B21-2.svgMUTCD R3-7L.svg
slight_left slight left turn (only)
sharp_left sharp left turn (only)
through going straight through (only) Richtungspfeil Geradeaus.jpg France road sign B21b.svgStraight only.svg
right right turn (only) Richtungspfeil Rechts.jpg MUTCD R3-5R.svgZeichen 209-20.svgMUTCD R3-7R.svg
slight_right slight right turn (only) Autobahnkreuz A24 - A10 bei Potsdam - Leipzig - geo.hlipp.de - 3191 crop.jpg
sharp_right sharp right turn (only)
left;through / through;left left turn & through (only) (the variant of used values is to be discussed, see table of some distribution examples here: distribution) Turn-left-through.png
right;through / through;right through & right turn (only) (the variant of used values is to be discussed, see table of some distribution examples here: distribution) Turn-through-right.png
reverse reverse/U-turn (only) U turn A2 Lithuania.JPG
merge_to_left the traffic of this lane has to merge with the traffic of the lane to the left of it (only) Merge To Left.svg US "lane reduction ahead sign" signRight lane ends, one lane remaining on the left, shown with one lane of oncoming traffic
merge_to_right the traffic of this lane has to merge with the traffic of the lane to the right of it (only) Vorankündigungspfeil.svg US "lane ends" signFahrbahn 2.pngFrance road sign C28-3.svgNederlands verkeersbord L5.svg
slide_left slide to left RU road sign 5.15.2 K.svg RU road sign 5.15.2 H.svg
slide_right slide to right RU road sign 5.15.2 I.svg RU road sign 5.15.2 D.svg
none there are no turn indications on this lane
This value could be skipped for a shorter format, so ||right is equivalent to none|none|right. Some people find the latter more readable.


Usually the turning indications of a road differ from lane to lane. To specify those indications for every lane, the :lanes suffix is used. For details about the :lanes suffix in general, see Lanes.

In short:

  • The key changes to turn:lanes=*
  • View the road in the direction of the osm-way.
  • Add the lane-values to the value, starting with the leftmost lane and ending with the rightmost. Separate each lane-value with a | (vertical bar)

If you want to describe only the lanes of one direction of the road, use either turn:lanes:forward=* or turn:lanes:backward=*. The key turn:lanes:forward=* describes only the turning indications on the lanes in the same direction as the osm-way. The key turn:lanes:backward=* describes only the turning indications on the lanes in the opposite direction as the osm-way; doing so view the road in the opposite direction of the osm-way for this.


There are three lanes on a one-way, and the leftmost lane will turn left, the rightmost lane will turn right and the lane in the middle will go straight through the next junction.



There are two lanes on the road in each direction. Those lanes running in the same direction as the osm-way are considered to be "forward"; the others "backward". The left lane of the forward direction will turn left and the right lane will go straight through and also turns right. The left lane of the backward direction will go straight through, the right lane will turn right and also continue straight through.




TurnExample6.svg lanes=3
TurnExample5.svg lanes=4
TurnExample4.svg lanes=3 (lanes=1 on ramp roads)
TurnExample3.svg lanes=4
TurnExample2.svg lanes=3
A3-Ring-StevensWoluwe.jpg Klettenberg, Köln, Germany - panoramio.jpg lanes=4




Bryan Housel has stated they are adding a visual turn lane editor to iD during July-August 2016.[2] This will likely make it into iD v3.0 which is still upcoming as of April 2020.