Forward by 24 hours upon crossing the International Date Line.įor anyone traveling eastward, they must set their clocks:.Back by one hour for every 15° of longitude crossed, and.People traveling westward around the world must set their clocks: Night and day is illustrative only daylight hours depend on latitude and time of year.) Circumnavigating the globe (Times are approximate, since time zone boundaries generally do not exactly coincide with meridians. Example depicting situation at 04:00 GMT Tuesday.
