I am trying to clarify the geographical extent of tz timezones. For the most part, the data files provide this information, but there are a few cases which are not entirely clear. Here are a few questions; once we figure out the answers, I'll be happy to propose updates to the tz files to capture the results (in comments, of course). Thanks in advance, Eric. --- Democratic Republic of Congo. Is it correct that: The zone Africa/Kinshasa covers the (pre-2009) provinces of Bas-Congo, Kinshasa, Bandundu, and Equateur. The zone Africa/Lubumbashi covers the remainder of the Democratic Republic of Congo. ---- Kazakhstan, using the names at <http://en.wikipedia.org/wiki/Kazakstan#Provinces>. Is it correct that: Asia/Almaty = Kostanay, Karagandy, South Kaz and everything east of them Asia/Qyzylorda = Kyzylorda Asia/Aqtobe = Aktobe Asia/Aqtau = Mangystau Asia/Oral = West Kazakhstan The Atyrau province is not mentioned explictly, and given its location, it should be in one of the last three time zones, but which one? --- Indonesia. Is it correct that: Asia/Jakarta is the island of Sumatra, the island of Java. Asia/Pontianak is the provinces of West Kalimantan (Kalimantan Barat) and Central Kalimantan (Kalimantan Tengah). Asia/Makassar is the island of Sulawesi, the Lesser Sunda islands (Bali, East Nusa Tenggara, West Nusa Tenggara), the provinces of East Kalimantan, South Kalimantan. Asia/Jayapura is the provinces of Maluku, North Maluku, Papua and West Papua. --- Uzbekistan. What is the boundary between Asia/Samarkand and Asia/Tashkent? --- Marshall Islands. What is the division into Pacific/Majuro and Pacific/Kwajalein? is the later just the Kwajalein island, as this 1993 NY Times article suggests? <http://query.nytimes.com/gst/fullpage.html?res=9F0CE1D6163EF931A1575BC0A9659...> --- Ukraine: what is the division of Ukraine in its four time zones, preferably in terms of the administrative divisions (e.g. <http://en.wikipedia.org/wiki/Administrative_divisions_of_Ukraine>)? --- Spain: Does the Africa/Ceuta timezone apply to all the "Plazas de soberania" or just to Ceuta proper? If the later, what is the time zone for the other places? (See <http://en.wikipedia.org/wiki/Plaza_de_soberan%C3%ADa> for a map.) --- China: the descriptions of Asia/Chongqing and Asia/Urumqui both include "west Qinghai". Shouldn't it be "east Qinghai" for Asia/Chongqing? The Asia/Urumqi zone is described as including counties of Guangdong. That seems awfully far to the east of the other areas included in that time zone. Inner Mongolia is divided between Asia/Chongqing and Asia/Shanghai. What is the division in terms of the administrative regions at <http://en.wikipedia.org/wiki/List_of_administrative_divisions_of_Inner_Mongolia>? Tibet and Xinjiang are divided between Asia/Urumqi and Asia/Kashgar. What is their division in terms of the administrative regions at <http://en.wikipedia.org/wiki/List_of_administrative_divisions_of_Tibet_Auton...> and <http://en.wikipedia.org/wiki/List_of_administrative_divisions_of_Xinjiang>? --- Greenland and Antartica: what would good areas for the zones? Should they be narrow (i.e. around "inhabited" places) or wide (i.e. form a partition of the land)? --- PS. I am still nibbling at a shapefile of tz timezones for the world, which I will make available eventually. Right now, I managed to reconstruct the bulk of it from the VMAP0 data, and thereby establish a clear traceability of the map.