On Sep 5, 2013, at 12:30 PM, Lester Caine <lester@lsces.co.uk> wrote:
Zoom in on http://maps.derickrethans.nl/?l=timezone,timezones&lat=52.485&lon=-1.890&zoo... the entire database of shape files needs to be replaced with the administrative boundaries from the OSM database,
To which *level* of administrative boundary are you referring? http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative Level 2 (nation-state boundaries) is obviously insufficient to handle the entire tzdb, and going down to, for example, the US's level 8 ("municipalities, including cities, villages, etc. Also incorporated townships (New Jersey, Pennsylvania.)") is equally obviously overkill in most cases. In order to use OSM to construct boundaries for tzdb zones, a *mixture* of administrative boundaries would be required, so that *wouldn't* constitute replacing tzdb boundaries with administrative boundaries from the OSM database, it would constitute *constructing* higher-quality tzdb boundaries from the administrative boundaries.