On Jul 3, 2024, at 10:54 AM, Ian Abbott via tz <tz@iana.org> wrote:
On 03/07/2024 08:11, viet le via tz wrote:
Hà Nội, as the capital city of Viet Nam, is the administrative and political center of the country. It holds significant historical, cultural, and socio-economic importance. Consequently, using Hà Nội as the reference point for the country's time zone would be more appropriate and align with international standards and practices.
The timezone identifier string for a region is based on the most populous city in the region, not on political centers. For example, the TZ database contains "Asia/Shanghai" (rather than the capital city "Asia/Beijing") for this reason. This policy is described in the TZ "Theory" document: https://ftp.iana.org/tz/theory.html
Some further examples of "the capital city is not the city whose name is used for the tzdb timezone the city is in": US: capital: Washington timezone city for the timezone the capital is in: New York Canada: capital: Ottawa timezone city for the timezone the capital is in: Toronto Brazil: capital: Brasilia timezone city for the timezone the capital is in: Sao Paulo China: capital: Beijing timezone city for the timezone the capital is in: Shanghai Australia: capital: Canberra timezone city for the timezone the capital is in: Sydney And, once again, I note that tzids Should. Not. Be. Exposed. To. The. Majority. Of. Users. If a user interface offers cities to choose from, It. Should. Not. Offer. Only. The. Cities. That. Are. Used. In. Tzids., it should offer a wider range of cities and map from the city to the tzid.