They also often follow state lines, but not always.
This is because it is on the eastern time of North America and is used by all other time zones in North America.
The actual borders on a time zone map have been drawn to correspond with both internal and international borders, and rarely match up exactly with the 15-degree time zone borders.
Clocks are set ahead one hour at 2:00 a.
That responsibility eventually shifted to the U.
Standardized time was instituted in 1883 by the U.