[OHM] Advice on modelling historical boundaries & where to keep them?

[Tim Waters]

OHM has been brought to people's attention from OSM when they have added
historic features which don't belong. I think this could be a classic
example of one such use case, yes.

OHM is for everything that used to exist, basically and this would include
past admin boundaries. Date ranges can be as basic as start_date and
end_date tags.

Regarding them being in OSM, I can see that some areas might still be
called or be defined by the non official status. In this case, the boundary
would still exist and there could well be conflicts with official ones.
It's a similar argument for disused and historic railway lines and Roman
roads which may still have their mark on the present day map.

Tim

On 18 February 2015 at 07:37, Jo Walsh <metazool at fastmail.net> wrote:

> A case recently came up for the DWG in which an effort to model
> historical administrative boundaries is interfering with geocoding
> results from Nominatim, and data deletion is resulting. The problem
> seems in part to lie in the use of admin_level to tag historical
> boundaries, without a clearly understood means of parsing date ranges
> for boundary validity. I see some wiki notes on historic boundaries
> here, but they seem partial and outdated in nature:
>
> http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dhistoric
>
> It's not purely a research question as there can be decent business
> value in historical boundary data, cf the self-supporting Vision of
> Britain Through Time", whose underlying data is unfortunately caught up
> in the issue of Ordnance Survey derived works, in part.
> http://www.visionofbritain.org.uk/ and that project did some
> investigatory work in Sweden and Estonia, I believe; I've lost touch
> with Humphrey Southall, the founder, since i moved on from research
> support work.
>
> Anyway, it seems to me as if OHM would be the perfect place to redirect
> people with a burning desire to map historical abstractions, in the same
> way that opengeofiction.net is an ideal outlet for people who must map
> fictional places which don't belong in the main OSM dataset. Does this
> make sense and is OHM as it stands a stable and long term resource for
> such mappers?
>
> I would appreciate any advice or opinions on the topic of historic
> boundaries in OSM from those who have been thinking about it for a lot
> longer than me,
>
>
> - Jo
> --
>   Jo Walsh
>   metazool at fastmail.net
>
> _______________________________________________
> Historic mailing list
> Historic at openstreetmap.org
> https://lists.openstreetmap.org/listinfo/historic
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/historic/attachments/20150218/818d69e6/attachment.html>