distance=* instead of pk=*
pk=* is French and not intuitive. I propose to use distance=* instead. See also: http://lists.openstreetmap.org/pipermail/tagging/2013-May/013539.html --Skyper 19:31, 20 June 2013 (UTC)
Kilometre as default unit
We should use the metric system as default. For milestones kilometre seems the right choice. --Skyper 19:31, 20 June 2013 (UTC)
- I think we should use whatever number is printed on the milestone and record it verbatim. If the units of that number is not the default (km), then we should add an explicit unit designation. T99 (talk) 20:53, 24 August 2019 (UTC)
How to specify two distances?
Most of milestones in Russia looks like two-sided metal flag. Each side of these flags have own distance, for two directions. For example milestones placed on Russian road M-5 “Ural” contains distances to Chelyabinsk and to Moscow.
Which of distance should I put to distance=* tag? Which tag should I use for distance of opposite direction?
- I also wondered this. I think a schema like distance:zero-point=* would work. F.e. distance:London=15.8 for the distance to London (with localised names, as they appear in the place node name=* tag).
- I ran into such milestones on a cycleway (it used to be a railway connecting Roeselare and Ieper, so it's very straight and long). Every crossing had a milestone, with the distance to Roeselare on one side, and the distance to Ieper on the other. --Sanderd17 (talk) 16:27, 21 November 2014 (UTC)
There is some idea on http://wiki.openstreetmap.org/wiki/Talk:Proposed_features/Milestones - use "milestone:forward" or "milestone:backward" attributes. But what direction is "forward" or "backward"?--Zlyh (talk) 08:36, 28 October 2015 (UTC)
There is some old discussion about milestone:
Node on the way or in the mark position?
- Real position. → ViriatoLusitano Portugal (Talk | Contribs) ← 00:05, 13 August 2017 (UTC)
- I would say on the highway. Otherwise we won't be able tell which highway it belongs to when we have 2 or more nearby highways. By using it as a separate node it will suffer the same problems from Key:traffic_sign#As_a_separate_node --naoliv (talk) 21:14, 24 October 2017 (UTC)
- Isn't this corrected by having a ref tag on the milestone with the highway ref it belongs to? → ViriatoLusitano Portugal (Talk | Contribs) ← 21:23, 24 October 2017 (UTC)
- Real position +1. And about the relation between milestone and highway...Why not using a new relation type? BTW, this page is changed to "The node should be part of the way that represents the highway." https://wiki.openstreetmap.org/w/index.php?title=Tag%3Ahighway%3Dmilestone&type=revision&diff=1493715&oldid=1437923 --Yellowsoar (talk) 09:52, 21 March 2018 (UTC)
- On the highway, because the sign has a property of a road. It is useless otherwise. The same as for traffic_sign=city_limit and highway=give_way. --Zverik (talk) 18:32, 29 March 2018 (UTC)
- Milestones mark a position on a road, as a distance from a reference point. Distance is usually measured along the center line of the road, which coincides with the way for a single-carriageway road. I would assume the majority of use cases to be about translating locations such as “km 36 on road A43” (frequently used by road administrations) into a coordinate pair, whereas few would care about where the physical milestone is located. Taken together, that would mean placing the node on the way for a single-carriageway road, and between the carriageways for a road with two separate carriageways. --Stanton (talk) 13:57, 30 June 2019 (UTC)
Use of ref=*
The wiki page currently states:
- ref=* is optional, only to be used if the milestone actually has a reference number written on it.
Recently, I had a discussion with someone who maintained that this tag should be the reference number of the milestone, not of the road.
I currently have the following use case: I get location indications such as “km 36 on road A43” (a notation frequently used by road administrations) and need to translate them into a coordinate pair. (I can handle cases in which results are a few meters off the road, and am also prepared to deal with ambiguous kilometric points.) For this I need to match milestones to their roads, which is very easy to do when there is a tag indicating the road reference number—whether that is ref=* or something else, as long as it is uniform. Without such a tag, matching becomes quite complex. It is still doable if the milestone tags are on the way, but for roads with separate carriageways common practice seems to be to place milestone nodes in the middle, between the two ways.
Also, I am not sure how frequent reference numbers for milestones are (apart from the reference number of the road being indicated on the milestone)—in which case the ref=* tag would hold something other than the road reference number. In the case of Poland, however, mileages are usually indicated on delineators with no road reference number, yet over 90% of the 35,000+ milestones in Poland have the ref=* tag set (87 milestones do not; of those that have, 97 are my own edits).
If we are talking about the road reference number, I wonder if it is that important to know that milestone 1 has the road’s reference number written on it while milestone 2 doesn’t.
I would therefore gravitate towards one of the following two alternatives:
- Use ref=* to indicate the road to which the distance refers, regardless of whether or not is is indicated on the milestone itself. This seems to be widely used already, even if it slightly deviates from the definition of ref=*.
- Introduce a new tag, say road_ref=*, to indicate the road to which the distance refers, regardless of whether or not is is indicated on the milestone itself. This does not clash with any usage I am aware of, but is not currently being used anywhere. (According to taginfo, road_ref=* is currently used 1,295 times, 99% of those cases are for TMC data.)
I'm using this tag for distance markers on golf courses unless a more suitable tag can be identified. For example: highway=milestone + distance=150 yd (pictured). T99 (talk) 21:21, 24 August 2019 (UTC)