There is also US/Pacific, which is just an alias for America/Los_Angeles. America/California is ambiguous, because there are several Californias in the "America

There is also US/Pacific, which is just an alias for America/Los_Angeles. America/California is ambiguous, because there are several Californias in the "America" area, which encompasses North and South America. https://en.wikipedia.org/wiki/Tz_database#Location https://en.wikipedia.org/wiki/Tz_database#Location > Country names are not used in this scheme, primarily because they would not be robust, owing to frequent political and boundary changes. The names of large cities tend to be more permanent... > Usually the most populous city in a region is chosen to represent the entire time zone, although another city may be selected if it are more widely known, and another location, including a location other than a city, may be used if it results in a less ambiguous name. Basically: globally, regions and countries change, but cities are much slower to change. They don't just pick up and move like borders can.