Transcription
A map of the world with vertical lines marking the time zones from UTC-12 to UTC+12. It has a legend:
Wrong Time
"Natural time zones" are 15° in longitude. Land in red observes a time other than the zone it lies within. Smaller islands depict their 12 nautical mile territorial sea, for visual effect. In some cases this includes a state's archipelagic waters.
Plate Carrée projection, WGS-84 datum. December 2018 © International Mapping, all rights reserved.
It strikes me that the Middle East, central Europe, and south-east Asia are the best places for time zone accuracy, while western Europe, western Africa, and northern Asia are the worst.