Instead of having to infer this from the ruins being in the vicinity of a railway=dismantled, would it make sense to explicitly record it with something like ruins=railway_support_pillar?
At first glance this would seem like a win-win, but perhaps I’m missing something.
Note: I haven’t looked into whether ruins=railway_support_pillar (or equivalent) is in use. Conceptually though, it would make sense?
You would think there would at least be something for ruins=bridge_pylons or similar, as there should be a few of them?
& after checking TI for ruins + bridge:
bridge 384
bridge_pier 5
bridge_pillar 3
pedestrian_bridge 1
railroad_bridge 1
The problem with this is in distinguishing between the whole bridge (superstructure) ruins, and the still existing bridge understructure. The bridge piers themselves may not always be in a state of ruins, but are part of a bridge ruins. ruins= doesn’t allow this to be expressed. Using historic=ruins on every part result in multiple such feature. This doesn’t show the situation nicely. Therefore =ruins is best limited to ruins=bridge whole area, or collection of them.
There’s also no need for more disorganized ruins= , which should at least be in the already long list of historic= first. There are some historic=bridge , in support of the above method. The piers are physical structures, therefore bridge:support= + ruins=yes is enough, same as building= + abandoned=yes to describe how it exists now. If it’s really broken to unrecognizable, then a sole ruins:bridge:support= may be considered.
Fundamentally, man_made=bridge doesn’t include use info, surely for many good reasons. I don’t see a difference here. It would immediately fail for road-rail bridges, and bridges that have change between road or rail uses (although I could see some merit in showing what class of load the bridge was originally designed for). Bridges often carry utilities. This might be equally important or prominent in history, and the role doesn’t need to be diminished.
Furthermore, mainline trains or heavy rail, trams, and later metro are different. Using some railway doesn’t show what it is for, and will fall into the same defect as railway=abandoned still requiring abandoned= / abandoned:railway to be fixed. Again, it will fail for bridges that changed between different train uses. As a secondary concern, such railway terminology may cause it to be misunderstood as not including tramway or metro in the use of some languages.
If there’s truly a need to directly show what they are used for, maybe some form of train=yes etc is better. This allows the structure and function to be separated.
If the want is for relating them explicitly, type=bridge is purpose-built. That’s better than the generic and perhaps tricky =site , although some may want to debate whether ruins should still use type=bridge , or =tunnel for tunnels.
I agree with a lot of what you say, but what characterises OSM’s rules and methods is that we do not have a doctrinal adherence to rules and methods. We have a doctrinal adherence to “what works”. Encouraging contributors, rather than rulebook-ing them, is what works.
railway=dismantled is a lesser sin in the observation/inference sphere than (deep breath) proposed roads, maritime boundaries, all administrative boundaries come to think of it, bus routes, post/zipcodes, unsignposted road refs, the US Bicycle Route System, exactly what is a highway=tertiary (contd. p94).
Hook Norton Viaduct is much more clearly a dismantled railway than US 17 is a bike route. How anyone can justify mapping the latter but not the former genuinely baffles me.
It’s actually very easy to do that (even before posting here). Just search at taginfo for ruins, and filter by railway:
I have no problem with mappers connecting the past to the present in OSM. The past always lingers in some form. I contribute to both OSM and OHM simultaneously, often mapping two aspects of the same feature in tandem. In this manner, the two projects strengthen each other.
Ironically, the counterexamples you’ve cited include some types of features that the community chooses not to map, chooses not to map directly, or has a very uneasy relationship with. To the extent that we map any of these things, it’s because mappers have been able to make the case that they have some practical utility in a use case focused on the present. Case in point: giant time zone boundaries are technically verifiable based on a few signs here and there, and theoretically on a multitude of wall clocks, but practically speaking they’ve all been mapped based on a close reading of the legislation. For these boundaries, the issue of verifiability is really a distraction. It doesn’t take a lot of imagination to come up with the real justification, that these features are useful on a general-purpose map; indeed, they’re widely used in time zone selector maps.
Unfortunately, every time the abandoned railway issue comes to a head, it’s a case where the railfan has already engaged in self-censorship in a futile attempt at playing by “our rules”. I do find that sad. If we were to allow them to fully map what interests them, what we would have is OHM. (Whether to merge the two projects would be a topic well beyond the scope of this thread, and a bit of the tail wagging the dog.)
That’s not really a characterisation I recognise. I don’t map (or not) Hook Norton Viaduct out of self-censorship, I map it because I see “dismantled railway viaduct”.
What’s useful on a “general-purpose map” isn’t and shouldn’t be a principle for OSM. There were adequate general purpose maps in 2003 and there are many more now, these days often produced by some guys in Mountain View. OSM’s strength has long been in specific-purpose maps.
As always, it’s about harnessing the many different enthusiasms of millions of contributors, rather than corralling them all into a singular vision which they may not share. There are lots of things I don’t like in OSM, including many I don’t think should actually be there at all (mutter mutter East Coast Greenway mutter), but I don’t start threads proposing they should be removed. Why? Because the cumulative effect of motivated, empowered contributors is much more important than my own personal interpretation of data purity - an interpretation that may not be shared exactly by anyone else. I would far rather write one line of code to say “don’t give the East Coast Greenway a routing uplift” than write 1000 lines of forum spleen, thereby putting off countless contributors, to say “don’t map the East Coast Greenway”.
And here I am, once again having been sucked into writing 1000 lines of forum spleen to defend a status quo which works. Hey ho.
It’s no coincidence that the Ordnance Survey, the inspiration for OSM in so many ways, actually uses the phrase “Dismantled Railway” on its maps:
(extract from OS 1:25k map of Hook Norton, used here under fair dealing provisions)
…I’m a bit worried that I’m giving the impression Hook Norton is only remarkable for its viaduct. Hook Norton is chiefly remarkable for its beer. If you like beer you should visit. (I don’t. I like viaducts though.)
I do find that sad. If we were to allow them to fully map what interests them, what we would have is OHM.
I fully map what interests me and what I have is the New Adlestrop Railway Atlas 
I bring an example to better understand why I think that razed railways has been mapping wrongly some time.
Hook Norton Viaduct has clear remains so I expect that extreme minority would oppose mapping it.
Railfans are problem where they map bridges/railways/stations in places where all remains are utterly eradicated.
Potential confusion is caused by some people using “railway=abandoned” for “some traces are remaining” and “railway=razed” for “nothing at all remains in place of former railway, all traces are gone”.
While Proposing to deprecate railway=razed and railway=dismantled - #64 by Richard describes a different use of tags (and I would love if this tags would be used only in such way).
(similar in size to people who wanted to limit name to names signposted on physical signs, replace name tag by using wikidata tag where names would be stored and similar fringe ideas)
Well, what remains is a terrain feature that runs for miles and miles, even including bridges with very low ascent/descend. For one this is still visible (“hello” to the principle you quote) and second this may attract hikers and bikers, i.e. has practical impact.
Perhaps, then, I’m reading too much into this discussion based on other flareups that have happened on the mailing lists and Slack, involving well-respected community members who wound up demotivating everyone else by their idea of data purity. To paraphrase: “You must consult me before touching any of the rails I’ve mapped, because I know a lot about this subject.” Does anyone recognize OSM in this proof by authority? I don’t, and every time this issue flares up, I have less sympathy for those who take this approach to defending their turf. To be clear, I greatly appreciate that folks here on the forum have been much more magnanimous; if only that were always the case elsewhere.
We may not agree on the precise contours[1] of what constitutes a “general-purpose map”, whatever that is, but why spend all this energy defending a small subset of rail history when the real deal is such a greenfield waiting for our attention? If someday OSM feels FOMO from all the rich content in OHM and relents on this point, we can all celebrate.
Don’t look now, but we don’t map contour lines either, and those are essential to some widely used OSM-based maps. ↩︎
Yep. There are two (IMO) important nuances to this though.
One is that “all traces are gone” is in the eye of the beholder. A subject specialist may be able to see traces where a casual remote mapper couldn’t. In this case we should always defer to the subject specialist. OSM thrives (I’m repeating myself here) by collecting the knowledge and enthusiasms of subject specialists.
The other is that mapping an absence of something can in some circumstances be valuable information. If a railway trackbed is mostly in evidence, but it has been bulldozed for 100m by a motorway crossing[1], then railway=dismantled is actually pretty useful to say “hey, this bit of the trackbed is the exception in that it has gone”. This is personally how I’d judge @Mannivu’s example - if significant other parts of the tramway are still extant then it’s worthwhile to say “this bit has been blatted”; if the tramway is almost entirely lost then I wouldn’t.
An analogous situation happens fairly often in the UK, where a public right of way (the legally defined path) crosses a field, but the actual path as walked by people goes round the edge of the field. In this case it’s useful to map the PRoW in a way that conveys “there is an absence of a path here”, because the presence of a path is what people would otherwise expect.
As always, these are my own personal judgements. Other people might prefer having no way in the “blatted” case, for example. I believe it’s more important to foster community than impose my own judgements on other mappers, and I would hope others take a similar approach.
…I could link to a subreddit here which conveys my view on car culture but won’t because its name would set off various alarms ↩︎
Hi,
As always, it’s about harnessing the many different enthusiasms of
millions of contributors, rather than corralling them all into a
singular vision which they may not share. There are lots of things I
don’t like in OSM, including many I don’t think should actually be there
at all (mutter mutter East Coast Greenway mutter), but I don’t start
threads proposing they should be removed. Why? Because the cumulative
effect of motivated, empowered contributors is much more important than
my own personal interpretation of data purity - an interpretation that
may not be shared exactly by anyone else.
This lovey-dovey line of reasoning (in a similar discussion on the
German forum someone said “live and let live”) could, in this
unqualified form, be used to support any number of really damaging
mapping activities in OSM.
Of course we all want to be friends and be happy together with our great
project, and have a nice time and a fulfilling hobby, attract new
contributors who add useful data and do new and unexpected things with
OSM. Yay for world peace!
But the individual’s freedom to map what they fancy must find its limit
where their activity hinders that of others, and for me that point is
reached when someone draws a railway line across the center of the city
just because there used to be railway before the apartment blocks were
built. (This has actually happened in the city where I live.)
And this is not something that you can fix with “writing a line of
code”. On the German forum the abandoned railway enthusiasts have gone
so far as to say “well if you find that this is a problem for your
mapping, just set your JOSM filters correctly” - and certainly “having
to install JOSM and fiddle with its filters” is not the path to
“harnessing the many different enthusiasms of millions of contributors”.
Bye
Frederik
As I said above, I’d love to take data from both OSM and OHM. It sounds like I’d need to take some types of features only from one, and some only from the other. Technically that’s doable, but it does mean that all railway=dismantled etc. would need to be moved from OSM to OHM. It would appear based on posts above that that isn’t going to happen for licence compatibility reasons.
A solution would be to for the people who hate seeing railway=razed and railway=dismantled in OSM to resurvey all these features from OHM compatible sources and add them to OHM themselves. That would be a lot more work than creating long forum threads on Discord and here, so it’s unlikely to happen.
If that’s not an option then a discussion about individual features does make sense. Hook Norton Viaduct does make sense to map in OSM as something. We can discuss the best “something”, but what’s in OSM now is one good option. The “railway replaced by a lignite mine” makes far less sense to map in OSM (OHM might be the perfect answer there, but someone needs to do the work of adding it). In between the two are things like this - where there’s nothing left but it’s really quite obvious when stood at one end where it went.
Obviously a “discussion about individual features” is pretty much what the current status quo in OSM is right now. You might not like the way that some things are mapped (or even that they are mapped at all), but like we all do all the time you need to just Deal With It and carry on.
Hi,
One is that “all traces are gone” is in the eye of the beholder. A
subject specialist may be able to see traces where a casual remote
mapper couldn’t. In this case we should always defer to the subject
specialist. OSM thrives (I’m repeating myself here) by collecting the
knowledge and enthusiasms of subject specialists.
I disagree. If you add stuff to OSM that only subject specialists can
understand and handle, it will get broken, because like it or not, OSM
is a project of mediocracy. A project for the masses. Everyone can and
will edit it, and creating things in OSM that carry warnings “DO NOT
EDIT! SUBJECT SPECIALISTS ONLY!” curtails the ability of the many to
participate. If there’s stuff in OSM that I do not understand (and
cannot verify on the ground because special knowledge or equipment is
required) then I will either refrain from touching it (even if there
would be good reason), or I will accidentally break it.
That’s also why we try to have human-readable tags - we must build our
project so that everyone can participate, and not have “here be dragons”
areas that only specialists may enter. It’s bad enough already with
things like public transport or complex junctions with turn lanes and so
on. But adding stuff to OSM where any average person going to the place
would say “I see a few trees and a cycleway” but instead it’s a former
railway which anyone who can smell the amount of iron dust in the ground
will attest to - that won’t work, it will break, and it must break if
non-iron-sniffers are to be allowed to edit.
Bye
Frederik
I mean, really?!
I get the idea in principle. But I have never found a lone pixel-width railway=dismantled to encumber my editing. Not like administrative boundaries which are an enormous PITA when trying to do any sort of highway or waterway editing. Whoops, this river meander has been cut off due to floods, I’m now going to have to spend half an hour repairing the various boundary relations after remapping the river.
I’m sure you wouldn’t have posted if you didn’t find it a problem but… it’s so far from my experience I’m just surprised. Hey ho.
certainly “having to install JOSM and fiddle with its filters” is not the path to
“harnessing the many different enthusiasms of millions of contributors”.
I am going to frame this and put this up on the wall as “the moment when Frederik accepted that JOSM is not necessary for mapping”
Remember, the licensing barrier only goes in one direction. There’s nothing preventing the two datasets from intermingling in postprocessing or even while editing OSM. At a glance, this sounds like the sort of conflation task that many data consumers already perform when joining OSM data to other data sources. For example, for better or worse, Overture Maps takes an OSM building, falling back to a non-OSM building if it doesn’t intersect any OSM building. Overture doesn’t need to ram the entire Microsoft building dataset into OSM or vice versa in order to obtain a more comprehensive building layer. Microsoft buildings are ODbL-licensed, like OSM, but other maps use the same approach with public domain address and waterway datasets as well.
Granted, this conflation strategy isn’t foolproof. Sometimes OSM mappers have gotten the scoop on a demolished building before other datasets have updated, so in the absence of anything in OSM, Overture revivifies the building. This is why I’ve tended to retag demolished buildings as demolished:building=*, in the hope that a data consumer will consider it in its conflation strategy. If this is anyone’s reason for mapping completely obliterated railways – that a data consumer would otherwise backfill it from a third-party layer of severely hallucinated ML-detected railways based on outdated imagery – then I concede the point. But then we get into the question of how long to keep a demolished building around before it blocks a newly built building that we didn’t notice.
If problem would be limited to this then it would not be significant trouble…
But: sometimes these are far more dense networks or long gone railway buildings are also being mapped.
Or entire railway yards.
Or this likely not surveyed on the ground edit adding entire network of logging railways. Likely at least in part having no trace anymore on the ground.
Also, what worries me is if that is being seemingly accepted and not removed in time then we will have more classes of similar data added by people thinking it is welcomed.
As I understand OHM is fine with mapping 40 different reconstructions how specific castle could look like in XV century. But one of nicer parts of OSM is that in the end if there is conflict then on the ground situation resolves it.
That is impossible if people argue which reconstruction is more accurate (not sure how OHM deals with it).
And I live in a city with more than thousands year of history, with so many destroyed buildings that land was raised by meters and to go into older churches after centuries of buildings being torn down you go downstairs rather upstairs.
Mapping all buildings ever existing - or just road network changes over hundreds years - would ensure that data editing would be impossible. And even just mapping now gone cargo railway stations would protect some areas from editing by anyone who is not a JOSM expert.
In the end we would remove it - but we will have even more disappointed people that would get months/years of their effort removed from OSM.
Did you try asking the contributor there (a) what is left on the ground (b) if not, whether they considered OHM and (c) if they did why they didn’t use it?
Yes, changeset comment 10 days ago, their latest edit is 22 days ago so for now I am waiting before doing anything more like reverting this edit. That is my typical first step in such cases.
If they will reply in way indicating no survey being made (mapping from old maps alone) or give reply that these railway are utterly gone I will surely recommend OHM.
