International Date Line

Line dividing one calendar day from the next

The International Date Line (IDL) is the line extending between the North and South Poles that is the boundary between one calendar day and the next. It passes through the Pacific Ocean, roughly following the 180.0° line of longitude and deviating to pass around some territories and island groups. Crossing the date line eastbound decreases the date by one day, while crossing the date line westbound increases the date.

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