Linked from

The 21 pages that link to International Date Line, each with the reason it gives.

• Gregorian calendarRelated: Global civil use of Gregorian dates still depends on local time zones and date boundaries.

• LongitudeRelated: It lies near 180 degrees longitude, but political borders make its path differ from a meridian.

• Bering StraitRelated: It passes between the Diomede Islands, giving their nearby communities different calendar dates.

• CalendarRelated: Global date coordination requires a rule for deciding where one day begins before another.

• Time zoneRelated: Crossing it changes the date as well as local clock time.

• KiribatiRelated: Kiribati shifted the line’s course in 1995 so all its islands share the same date.

• Calendar reformRelated: It adjusts the placement of civil dates globally without redesigning the calendar’s year.

• CircumnavigationRelated: Voyagers must account for its date change when recording a complete global route.

• Daylight saving timeRelated: Seasonal clock rules add further complications to date and time coordination across regions.

• MeridianRelated: It roughly follows the 180-degree meridian while deviating around political and geographic regions.

• Prime meridianRelated: It lies roughly opposite the prime meridian in the longitude system.

• Magellan expeditionRelated: The returning survivors’ day count differed from Spain’s, an early sign of the effects of traveling westward around Earth.

• DayRelated: It coordinates civil dates across a rotating globe.

• Line IslandsRelated: Kiribati shifted the date line eastward so its islands share the same calendar day.

• New Year's EveRelated: It shapes the sequence in which places enter the new year.

• MidnightRelated: It shows that the date boundary depends on geography, not one worldwide midnight.

• 180th meridianRelated: It follows the 180th meridian across much, but not all, of the Pacific.

• Eastern HemisphereRelated: It follows much, but not all, of the 180th meridian.

• Chukchi PeninsulaRelated: It passes through the Bering Strait near the peninsula and separates the two Diomede Islands.

• History of navigationRelated: Global travel and longitude-based timekeeping required a convention for changing dates.

• Hemispheres of EarthRelated: Its course highlights the distinction between longitude boundaries and hemisphere labels.