[tz] tzdb data for North and Central America

Brian Inglis Brian.Inglis at SystematicSw.ab.ca
Wed Jan 15 22:28:20 UTC 2020

On 2020-01-13 09:15, Jeffery Nichols wrote:
> On Fri, 10 Jan 2020 at 16:51, Paul Eggert wrote:
>> Thank you for those corrections. I installed the attached patch to tzdb's
>> development version and these fixes should appear in the next release.> Great! I was also wondering whether anyone on your team has more data about what
> towns were part of America/Nipigon. I'm trying to map all of the Canadian IANA
> zones on OpenStreetMap. Your tzdb mentions that Nipigon was the largest town in
> its zone, which suggests that the zone wasn't limited to Nipigon town
> boundaries, but it doesn't give any clues about what other towns were found to
> follow it.

Look at the sites http://efele.net/maps/tz/canada/ and
https://github.com/evansiroky/timezone-boundary-builder for Canadian boundary
info and background; search in the mailing list archive from 2006 back for
Nipigon and Ontario, and look in zone.tab and northamerica for comments about NW
Ontario in context:

$ egrep '^CA\s+.*\s-\sON' /usr/share/zoneinfo/zone.tab
CA      +4339-07923     America/Toronto Eastern - ON, QC (most areas)
CA      +4901-08816     America/Nipigon Eastern - ON, QC (no DST 1967-73)
CA      +4823-08915     America/Thunder_Bay     Eastern - ON (Thunder Bay)
CA      +484531-0913718 America/Atikokan        EST - ON (Atikokan); NU (Coral H)
CA      +4953-09709     America/Winnipeg        Central - ON (west); Manitoba
CA      +4843-09434     America/Rainy_River     Central - ON (Rainy R, Ft Frances)
$ less '+/Ontario|Nipigon|Atikokan|Rainy_River|Thunder_Bay' northamerica

If you can't find an online searchable tz mailing list archive, you can download
about 18MB+ of archives starting from


to the current month, gunzip to about 70MB+ of posts, import them into a folder
in your mail client for convenient searching, and subscribe to the mailing
list(s) to keep your local archive up to date.

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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