What's the point of razed:aerialway?

General talk
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I get the idea of abandoned:highway etc. Those are actually often still visible in the landscape and hiked on by adventurers etc. But what’s the point of mapping razed:aerialway and similar tags, that stay around forever in OSM sometimes? I thought we map what we see? A decomissioned aerialway leaves no traces, there’s nothing on the ground (if anything, you can map razed posts). I get that someone would argue, that it’s “historical data”. It’s that, what we map, too?

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Recently razed aerialway may have no traces whatsoever on the ground but may be visible on aerial imagery. See Lifecycle prefix - OpenStreetMap Wiki

if you know of cases where it is utterly gone and not visible on standard aerial imagery it should be deleted

if you know about any cases and for some reason you are scared by deleting them, you can list some example in this thread and I will delete them (after verification on aerial and by checking object history and/or asking original mappers)

but if you know it is utterly gone and not visible on standard aerial imagery - I would encourage you to delete it

and those can be mapped on OpenHistoricalMap

more widely a bit: current verifiable state, which may include for example unsigned but known names

and some metadata like fixme= and temporarily kept razed:* etc

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It can be kept also due to pollution (to remember what it was) and simply because the place is still referred/known there. For instance, you have a Airport Road driving there.

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if no on-the-ground visible traces are present, that can be spotted by regular people, it should be deleted from OpenStreetMap

if someone is interested in past objects leaving traces as detectable pollution levels requiring expert analysis it is fit for OpenHistoricalMap mapping and out of scope for OSM

then it probably also should have place=locality name= at least if it is carrying name

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Also worth noting that if the latest imagery is a little blurry, the traces may not show up in the imagery even though they are still visible on the ground (e.g. weeds growing through concrete). So it’s worth taking care with deletion, if the current imagery is not as good quality as the last imagery that did show the remains of the aeroway.

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on the other hand if someone mapped it as razed: then it is are already marked as having no on-the-ground traces, and kept solely as some aerials are outdated (or preserving it as tagging for renderer)

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[quote=“Mateusz_Konieczny, post:4, topic:147429”,
then it probably also should have place=locality name= at least if it is carrying name
[/quote]

Not against that, in those cases I keep just a node (that what belonging to the feature, moving it to the centroid), so razed:* plus place, and the common node makes easy to retrieve the old geometry.
Well I was not using place, just the object and using the same prefix for the name (I wanted to make it searchable but not visible, in fact it’s not searchable by Nominatim).