Why Are Some Time Zones 30 Minutes Off Instead of an Hour?

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Images

World map showing standard time zones, with each zone shaded and labeled by its offset from Greenwich Mean Time. The International Date Line is marked with a bold, zigzagging line in the Pacific Ocean, and variations for half-hour and other non-standard offsets are indicated. Continents, major countries, and oceans are labeled for reference.

Why Are Some Time Zones 30 Minutes Off Instead of an Hour?: Media

Learn why the world’s time zones can be disorderly.

Images

World map showing standard time zones, with each zone shaded and labeled by its offset from Greenwich Mean Time. The International Date Line is marked with a bold, zigzagging line in the Pacific Ocean, and variations for half-hour and other non-standard offsets are indicated. Continents, major countries, and oceans are labeled for reference.

World time zones

A time zone map showing standard time zones and the International Date Line.

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