[Talk-GB] Admin Boundaries and OS OpenData BoundaryLine

[Ed Loach]

> It should only be attempted by an experienced mapper who is
> familiar with
> revert and other advanced techniques and can follow the guidelines
> on the
> wiki. The potential to break something is very great, so I would
> question
> making converted data available. Any conversion needs to build the
> relations
> so use something like 'ogr2osm' to create .osm files - a
conversion to
> GPX
> will not do this.

I'll second this. I used to run a boundary validation routine daily
on the British Isles extract from Geofabrik. I stopped it at the end
of March when I was expecting there to be no new extracts until
after the licence change completed, but this thread had me run it
again today. Previously I was fixing broken boundaries if they
remained broken more than a week (in case people were still working
on them), but towards the end of March decided to wait until the
licence change process was complete as that is likely to break some.

Anyway, at the end of March there were 16 admin boundaries listed
here:
http://www.loach.me.uk/osm/boundaries/
(includes false positives at admin levels 2 and 4 as not all
required ways are in the extract). As you can see this has roughly
tripled in the last two months. Whether this is remapping stuff that
has caused it or not I don't know.

Ed

PS: Note in some cases the "break" might just be an inconsistent use
of roles on member ways.