[Tagging] [OSM-talk] Should we map things that do not exist?
matkoniecz at tutanota.com
Mon Jun 8 11:16:03 UTC 2020
Jun 8, 2020, 12:50 by dieterdreist at gmail.com:
> Am Mo., 8. Juni 2020 um 12:28 Uhr schrieb Mateusz Konieczny <> matkoniecz at tutanota.com> >:
>> Jun 8, 2020, 11:39 by >> dieterdreist at gmail.com>> :
>>> Am Mo., 8. Juni 2020 um 11:20 Uhr schrieb Mateusz Konieczny via Tagging <>>> tagging at openstreetmap.org>>> >:
>>>> On 6. Jun 2020, at 00:04, Volker Schmidt <>>>> voschix at gmail.com>>>> > wrote:
>>>>>> I do object strongly to the invitation to remove the razed/dismantled-railway tag in the case of railway tracks have been replaced by roads with the same geometry.
>>>> Add I have no problem with removal of them.
>>> this is fine, we do not have to share opinions on everything. But we should be cautious to not misrepresent community consensus in the wiki. It doesn't appear to be an universally shared conviction that you can remove these objects of which the traces are less evident than of other things.
>> Can you edit wiki or link problematic page and quote text that should be changed?
> the reference is Volker 6/6/2020, 0:04:
>> Nevertheless the wiki page >> Demolished_Railway <https://wiki.openstreetmap.org/wiki/Demolished_Railway>>> was completely rewritten on 07:17, 27 May 2020 by >> Mateusz Konieczny <https://wiki.openstreetmap.org/wiki/User:Mateusz_Konieczny>
>> In particular the wording
>> "Here railway is gone without any trace in terrain except possibly road alignment. Its course is well documented, but such historic feature is out of scope of OpenStreetMap, should not be mapped and should be deleted if mapped"
>> in the caption of the first picture is certainly something we were talking about, but had not agreed upon.
I changed it now to
"Here railway is gone without any clearly identifiable trace in terrain. Its course is well
documented, but such historic feature is out of scope of OpenStreetMap, should not be
mapped and should be deleted if mapped."
now, without taking position on road alignment issue. Is it OK? If not, how it should be changed
to reflect general opinion?
> Lets say that there was a castle and was replaced by a sport pitch, and place looks like
>> this nowadays (a theoretical example):
>> Castle is remembered. Is such castle mappable? In my opinion would not be as there are
>> no identifiable traces (possibility of archeological excavations are not really changing this).
> I do not know if this is a real example (you say it is theoretical)
This specific is 100% theoretical, I searched for "football pitch" and taken the first image.
> So even if this would be the only reason, there would have clearly been traces of the castle, although not visible on the ground (but below).
I am 100% OK with mapping such traces as visible on the photo, but mapping building
as it existed in the past seems wrong to me.
Mapping underground remains seems terrible idea to me - older cities have entire layers,
meters of them of such traces.
In extreme cases so many remain were accumulated to change a geography:
https://en.wikipedia.org/wiki/Tell_(archaeology) is an entire hill of
"accumulated remains of mudbricks and other refuse of generations of people living on
the same site for hundreds or thousands of years (...) can be up to 30 metres high."
Opening gates to mapping all such former objects is a bad idea.
> But there are other, less direct, traces. For example the castle left traces in the urban structure, the main arterial road bends in front of the castle, and it did so also during the time when the castle wasn't there. And some buildings around it have always been referring to the castle, e.g. the building for the imperial guards and horses. Also the name of the bridge (castle bridge / Schloßbrücke) was always referring to the castle.
And if we decide that mapping objects with this kind of traces can be mappable then we de facto
allow to map any historic objects.
Mapping object just because it left any trace at all, or related name remained is a bit too much.
I am OK with mapping if there are still identifiable trace (even road alignment if it is actually clearly
recognizable as former railway).
But if there is road and one is unable to distinguish between
"former canal" and "former railway", "destroyed fortifications"
and "not constructed along geometry of a former object"
then mapping such canal/railway/wall is mapping of something so gone that out of scope of OSM.
BTW, thanks to this discussion I learned something about history of my city what was interesting.
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