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 I see some wiki notes on historic boundaries here, but they seem partial and outdated in nature: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 [email protected] _______________________________________________ Historic mailing list [email protected] https://lists.openstreetmap.org/listinfo/historic
